This Porsche Melted my BRAIN ('84 928S No Headlights - Part 1)
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- Опубликовано: 7 сен 2024
- Welcome to the world of Vintage European Technology.
This 1984 Porsche 928S runs and drives fine, but the brakes are dragging and it has a LOT of random ELECTRICAL issues...
-No Headlights
-No Blower
-No Intermittent Wipers
-No Power Locks
-No Dome lights
-No Power Tailgate Release
-No Cruise Control
-Can't Close Sunroof
HOLY CRAP!
After taking care of the sticky rear brake calipers, let's figure out the HEADLIGHTS.
Should be pretty EASY, right?
No computers involved, just switches and relays.
This Porsche proves otherwise and MELTS MY BRAIN. Ouch.
Enjoy!
Ivan
Crack open the relay box, it's either bad solder joint on one of the transistors or a blown transistor. Considering it is from 84, it's probably all through hole components, easy to fix.(I hope 😅)
These diagrams are common in Europe, Ive repaired everything from underground locomotives to construction plant. once you get used to them they become less difficult. Enjoy your videos. Regards from UK.
I agree with your comments n the diagrams. They are difficult at first but once you are familiar with them. German engineering definitely is complicated but produces fine products
This what I was thinking, I'm sure these made perfect sense to the German engineering team that made them. its almost like trying to read something in a foreign language.
When looking at a component (module or relay), Is there a trick or abbreviation to tell which pins are power, ground, control, and output? or do you have to trace each pin?
@@David-lq2xg Hi David, on the underside or side of the relay there is usually a pin diagram or pin numbers 85 and 86 are the coil pins 30 is the main input,87 is the switched pin and 87A is a changeover pin. If you look at the pins they should be marked as mentioned. Type A pins are diagonal type B relay ( common type ) are top to bottom. Modules I go to manufactures data sheets.
@@terryh8421 Thank you, Terry. How about the switches, such as the one shown at 11:36 (light switch).
Bought a nice '88 S4 back in 1995 in Tampa at auction, for $7500 I may ad. A few days later I head back home 1000 miles north. A few hours into the drive it starts raining. Hit the wiper switch and get nothing. Learned that if I kept it over 60, the water would just sheet over the windshield and I could see good enough. Then around 6 pm it was getting dark so I hit the headlight switch. The lights illuminate but they are pointing at the moon. The tail lights worked fine, so I figured as long as there is somebody at least 500 feet in front of me, I could tail them in the dark. So that's what I did, for six nerve wracking hours one night on I95. One thing I learned was you don't really need wipers at night. Something about daylight and water droplets make it much easier to see through the windshield when its dark. And the problem? Don't remember exactly but the two systems were on the same circuit and it was something simple like a fuse or corrosion on the relay terminals.
This is a seriously over engineered old school relay system that doesn't have to be that way. This brought back memories of older Volvo 240's using this funky lighting system failure sensor. Crazy mind-blowing stuff they came up with back then.
I actually have a Volvo 240 in my shop that doesn't have break lights,traced it down to that sensor. I handed it the service writer and said good luck 😂
@@85jmccoy find the wiring diagram for the sensor, gut it and replace it with jumpers, its just a bunch of nested coils around a reed switch. I never had one cause the lights to fail, mostly they just always lit the 'bulb out' indicator.
@@85jmccoy Yeah. It commonly is the taillights on those things causing that sensor to fail. And I believe it's because of that membrane PCB that they use on those taillights that can ultimately put too much of a strain on that sensor when they crumble.
I worked for a gentleman that had a Ph.D. in electrical engineering and delighted in troubleshooting and fixing complex systems. We had a problem with a 1979 Porsche 911 that involved the Bosch ignition computer. He worked on it for about 4.5 hours and then gave it back saying, "This should work now." I asked, "What did you do?" His answer was, "Typical German engineering - too many parts." "I took some of them out." It worked and the owner reported the car accelerated faster and got better gas mileage.
AMAZING LOL
To boldly go where no man has gone before.
“FASCINATING” 🖖
8-pages ALDATA.........1-2pages Mitchell......For over 40 years in the business. Electrical is the only labor that cannot be found in flat rate estimated time. Mitchell On Demand FAR exceeds Aldata, and I have NEVER found error with Mitchell...absolutely amazing..
To be honest, I kinda prefer these complicated relay setups to a box with a computer in it doing some mystery logic. You can follow the logic through the circuit and identify the actual fault rather than "oh well, the computer must be dead".
I agree, sort of. I think we do use computers too much for some functions. But I'm not sure how you'd design a modern car this way. Half the weight would be relays and wire. There have been several cases on this channel where I and at least one other person noted the simplest fix was grabbing a microcontroller like an Arduino and hacking a little code. Here, if the relay can't be fixed or replaced, you could wire up a set of relays to replicate the original, do the same thing with mosfets on a perf board, or grab a microcontroller. The logic isn't more than a few handfuls of lines of code.
That schematic is so ridiculous. Many years ago, I used to own the same year but a 944 model. The fuses would always have a poor connection to the fuse block and was a total electrical nightmare. Can't wait until part2. Thanks for the video, Ivan!
The headlight cleaner is most likely the optional wiper and spray system they had on some models, similar to the small wipers some Volvos also had on their headlights.
I’m all for taking it apart regardless just to see how simple or complicated it is inside!
Welcome to my world that was back in the 1990's with those crazy wiring diagrams . I changed my career path because of this and left it all behind.
I owned one of these for about five years and never had any problems. Sold it before I did. One thing I remember about the headlights, though: they did not turn on until the headlights attained their final UP position. There could be a physical switch in the headlight bucket system that is faulty.
I agree. There has to be feedback from that switch on the headlight bucket. Probably illegal to turn the lights on until the lamp is pointing straight ahead. Lots of laws in Germany.
I described the headlight lift and position switch in detail lol
@@PineHollowAutoDiagnostics Sorry - I didn't watch the whole video - which is extremely unusual.
Where the two small R clips placed in the caliper pad pins to prevent them falling out? The video skipped over that step.
I've made lost keys for those back in the day. Thickest key blade on any car that I recall.
My 92 corolla had a starter issue when engine is hot due to summer weather. It clicks but no start: Contacts are done recently. I want to check the starter relay and noticed the pins are not tight. Did a drag test and it was not too tight. Got all tight now. Hope the issue is resolved! Thanks for teaching auto electronics!
I remember a 928 had a local auto electrition stumped for a while. The cooling fans would not start up because of a slightly bad connection resetting the electronic controller. Hard to find without a storage scope. Storage scopes were very uncommon in the early 90s. The connection would load test ok and the fans would start with the load connected...but put it back to stock and they would not run. This car opened the door to a new world of problems across all makes.
Perfect timing of this upload to happen. I just sat down for these sort of goodness!!!
Hey Ivan, ATE makes some really good brake lube from Germany for the sliding portion of that brake hardware. I got some off of EBay but I used to get it from parts suppliers like O’rielly’s or Napa parts. Makes the calipers slide without hanging up. 😅
Nice case so far! I have been waiting for something like this for a short while. The cool thing that I find a lot of times with vehicles of this era is that so many components that are used in these "modules" or relays are pretty accessible through an electronics parts supplier or store. Radio shack was great when they were around. For the people saying that he should have lubed the pins, that's not actually correct. Lube on those pins can actually attract dirt, pad
dust, etc.. causing more problems than you hoped to avoid. Good job so far, looking forward to part 2! 👌🏼👍🏻
We in AUS have Jaycar for that type of electronics parts.
As a former VW tech, I agree about convoluted diagrams and ways of accomplishing certain functions.
My thought on the combination relay is bypass it altogether and split it into three relays for their separate functions if needed.
Then the diagrams become useless. Make it factory. Stick with the drawings.
@@MadmanJimbo I agree I had a 84 Nissan Gazelle with pop up lights & they were easy to work on the factory diags were easy to read when one wouldn't lift up there was a manual way to get it to do so & there was an explanation on how to fix it with an easy diagram to follow I stuck with the factory diags to fix it (there were other suggestions from auto electricians that were easier but as I do I'm thinking about who has to follow me.).
I was so happy when my friends wife blew his up some 30 plus years ago!! have fun IVAN!!
Kudos to you Ivan, I'd have taken one look at that circuit diagram picked up the phone and said to the owner "come and get your car".
That relay is interesting. I'd try pulling it apart to see if there's something that can be fixed. If not, I'd try breadboarding a solution with separate relays or mosfets. Not sure the complexity rises to the level of needing a microcontroller, but I always keep a few Arduinos laying around.
"This Porsche melted my brain." I haven't even watched this video, Ivan and already I am waving the BS flag. O.K. Now I have watched the video. Looks like we are going to get into some component repair; I have been waiting for that. When I first subscribed to "Motor Trend" magazine in 1983, these cars were all the rage. The 914, the 911, the 928, and the 944 were cars I really was a fan of; and I don't get gaga over cars. I think the 928 was front engine and rear-wheel drive; I think that engine was a V-8 IIRC. GREAT VIDEO!
front engine, rear transaxle for balance. 4.5-5.4L V8 depending on the year, I believe the 84 was the 4.7L version. close to 150 MPH in the smog equipped US version. more of a luxury GT car than a sport car.
@@geepeerces I would say close to a front/rear weight distribution of 50/50. Yes, they were more of a luxury GT; still better than what other manufacturers were offering at the time.
Back in the 70’s we used to hone the cylinder and replace the O ring and replace or polish the piston for that service, the independent garage i worked at required that be done at every brake job
“84 Porsche”…..Doesn’t that mean “Let’s try something we aren’t sure that works, just to see if we can make it more complicated than what we know works” in German? I’m sure I lost something in translation Ivan….😂😂😂😂. Ivan you never cease to impress my man. I believe the actual switch for the light is in the motor mechanism. Could,be wrong.
Knowing the DIN 72552 standard terminal nrs helps a lot understanding these old german diagrams.
Like 30 - battery power
56 - lights, 86a normally closed contact etc.
Check the wikipedia article about it
en.wikipedia.org/wiki/DIN_72552?wprov=sfla1
@ thank you for this info. It made things a little more clear also what DIN stands for.
Can I assume you put the Spring clips in those brake pad pins off camera?
Ivan, you've got our attention. See you in Part II. Thanks for Sharing! 🙃🙂
As an aircraft electrician for years, I liked to use about 5 different colors of highlighters, and for some schematics/wiring diagrams colored pencils(sometimes different colors could match a mode or state). It was similar to what you have here, we would have a couple of tables and the floor with the diagrams connected via clear tape. We would then have general systems manuals for theory of operation for some of the "magic boxes" wires would disappear into and come out of. This was to understand what was happening and under what condition the signal output would be changed and/or manipulated. It could get quite convoluted at times but in general, most of the time the material provided was pretty good. However, I did get pretty good at engineering dispositions to find the correct schematic that matched a particular aircraft or to clarify in what state the circuit matched a particular output. All that to say nice work those schematics are definitely not the most friendly I've seen! You've taken me back to my younger days! Cheers, Ivan!
Mooney aircraft. Whole aircraft on one sheet.
C17s and C130s are only a touch larger :) Mooney is a nice bird though!@@CharlesReiche
my favorite car from my teen years however i'm glad your working on it and not me. LOL
I actually understood that-must be dreaming. Betting you find a relay. Good show.
13 minutes in. My brain really hurts! You are amazing!
The wiring notation is standard industrial/machine tool wiring diagrams. Dealt with it for decades
My buddy lived next to a guy he had 10 of these at his house, they are interesting Porsche's
I love the little box with the bipolar transistor on it with about 6 wires connected to it. So clear as to what it does. Combinational logic , state machine , who knows?
Looks like bipolar disorder to me. Must have been the same bunch of guys that invented the Enigma encryption machine back in WWII.
The transistor is representing a smart power driver either in a TO-220 or SMT DPAK , D2PAK, there are many options for replacement. For the age of the module (smart switch pack) if there are any large capacitors these should be replaced as well. If there are several smart drivers it may be best to replace all of them if it looks like the PCB can withstand the repair.
Very nice work Ivan, I'll say brain meltdown.. you lost me when you first said "Porche".. lol
You would make a helluva auto electric teacher and, as a matter of fact, you already are with these videos. I worked as a tech back in 80s and this kind of diagnosis was typical. Every car manufacturer did wiring diagrams differently. I knew then these cars would be a nightmare for the future techs.
Electrical is one big issue with 80s vehicles... wait until these techs start trying to repair all those experimental fuel systems (to get around the Bosch patents) like variable venturi carbs, throttle body fuel injection, etc. Those cars were a nightmare then when parts were available.
I really enjoy your approach and bulldog attitude towards finding the real issue before firing the parts cannon.
I have a 1981 Subaru and I am trying to read the diagram. It is not as confusing as yours but it comes close. Thanks for this video. Paul
I feel your pain! Coloring helps but I usually break down and redraw circuit paths on a single sheet whenever its this broke up with unclear power distribution. Yes just make your own relay logic to bypass any non repairable "modules".
I'm feeling your pain bro. I bought a 928 back in the mid 2000's. I ditched the 928 engine and went LS via the Renegade Hybrid kit from Las Vegas. That was a piece of cake but i've had 2 mechanics and 3 auto elecs look at it. They all bailed. Well over a decade and still not finished, total price that would rival a small country. My son and i bit the bullet and took it for a burn up and down the street just for the fun value until we found the fans not connected. Never again. The biggest problem? One smarty pants electrician who cut the loom in total for a 'rewire'. Never ending drama ever since.
That's what happens when you're a fool with too much money
Great video. When I was ready to sell my 88 S4 my low beam went out then my high bream. That dual relay cost.$213. Other than that no problems but battery tender or.disconnect is your friend. Im selling it so it has to go.
🤯 Wow that is way over complicated for no reason. Hes got the right guy on the job 👍Cant wait for part two!
One of your strong points is that you stay on ther problem until you solve it, unlike a dealer that would replace some parts and then just give up
I was working on my wife's Subaru a couple months ago, and her brake pistons came out. Not on purpose but because I was an idiot. I had done the rear brakes and wanted to use the parking brake to help hold it on our sloping driveway to do the fronts. Well, I hadn't planned this out, so things got out of order and I forgot I had already removed one of the front calipers. Coming out of maintenance mode, the procedure is to pump the brakes. It wants to make sure there's brake pressure before coming out of maintenance mode. And that's when the pedal went to the floor. My driveway was a mess of brake fluid, and I know squat about calipers. I thought I had broken them, but it turns out you can just clean off the piston and reinsert them. And that's what I did. No problems since.
I remember once someone describing how many MILES of wiring are in a 928. I had an 85 and loved it!
I worked on an 84 928S about a year ago, and it had ALL of the exact same issues!! Hilarious. The headlight relay gets "out of sync" somehow (i realize that doesn't mean anything lol) but I believe the wiring to the headlight motor was the problem!! There is a SWITCH inside the headlamp motor that turns on the lamps only once they are in the UP position.
(Writing this before I watch the video, let's see if I'm right!)
Yes you are right... The light should not get switched on while the turning of the headlightshas not been finished. This would be not allowed.
Believe it or not parts are readily available for this car. There is a community of 928 owners that is very helpful also.
some parts -yes. but non of the "smart" multi-relays. there are for 944 and 911 but nothing new for 928@@netimage10s
Think of it as a safety feature so that high heat bulb isn't on and shinning into a closed space
A Porsche 928 with problems? Say is ain't so! I remember when I saw one brand new and I said to the driver, "that's a fancy Volkswagen you got there". Needless to say, he wasn't pleased. That rear hatch closing sounds just like the doors on a Cevy Chevette.
I thought that's what a wife is for!!😄
Great job again 👍
Greetings from Germany! I can say that wiring diagram is indeed ridiculous. My first car, an 81 Opel Senator was the same. I now own an 89 Chevy Caprice, diagrams are a dream. But let me tell you, my second car, 96 Lancia, those diagrams are even worse. Italian electric
You have a fantastic patience, Ivan! If it was my car, I would have just rewired everything from scratch, to be honest. These odd relays are almost impossible to get a hold of anyway.
The Porche that no Porche lover wanted the 928
I have an 87 944S and if my memory is correct…. Same type is setup. Popup headlights. Not as cool as the 928. In the day when one of those was coming up behind you at a decent clip.. you knew exactly what it was!
Nice video and diagnosis. People always claim old cars were so much easier to work on. 😂😂
those diagrams remind me of the MG wiring diagrams I work with. they are a mess like that with sigle letters for the wire colors and weird layouts. plus the only ones I have access to are crazy old photo copies that always seem to be faded in the most critical area.
Hard one
Head scratcher great diagnostic contents 👍
I had one of these perlexing problems with a 1984 Volvo 245 wagon. All the tracing in the cabin did not yield a consistent answer. Finally I found an engine ground strap out of sight that had been left off.
If it is the relay, then OEM would be the go if you can get it, or after market. I googled the part number and you can buy German made ones still. At least it will keep it in Factory condition for the next person. If it was an every day economy car, then sure, a modification would be okay if the part is cost prohibitive and the owner agrees. But this vehicle should be kept as Factory as possible. I do hope that is what you ended up doing.
I spray Fluid Film into those brake piston boots and it will free up any rust and prevent it from rusting in the future.
Once worked for RR and some circuits listed pinouts for each device and mapped each device to coordinates. Every reference was to coordinates, device and then pin. These were intended to allow wiremen to wire circuits without knowing anything about circuits. Each end of a wire was marked with its destination. Like yours, very hard to follow.
Ok, After following the "logic" from the manufacturers diagram because they never do anything complicated, I can understand why someone used a toggle switch , Good Luck Ivan , great first part.
Just when I was going to sleep, now to stay up another 23 minutes 🤣
Ivan I watched for 23 minutes only to find out there is a part 2 and I needed my beauty sleep 😴. I’ll look it for part two, please don’t do this to me again 😉🤣
Can’t even imagine how you would charge a customer for a repair like this? The amount of forensic electrical investigation is mind numbing? Not saying it’s impossible! And what a Porsche dealership would charge , would be astronomically infeasible!
You almost have to use that Ashtray to figure out what that insane diagram from Hell is saying 😮❗🧐
Ivan gotta love it. Hey nothing like a good/great challenge
I had heard back then, that some of these relay boxes were often having to be replaced. Not necessarily because of just
the headlights in particular. I've had my share of working on a 74 Fiat 124 Sport, 79 VW Rabbit, and 82 Porsche 924 and so
all three of them can indeed be nightmares to repair. Each and every one of these had nearly the same attributes. I can
only speculate that these relay boxes were all made by the same manufacturer. One of the biggest manufacturer's for
instrumentation and other components is I believe is VDO. May it be dash instruments, ignition switches and the rest.
But then there was Bosche also.
My brain is out.Thank you for a great video as always.
Yea seems to me the support circuitry for the npn transistor has a bad cap in it causing the thing not to latch.. or bad transistor.. either way i would bet you could find a replacement for cheap if not free if have some old circuit boards from stuff., bet its a common transistor like a 2n222….
WOW I got a headache just following along. Can't wait to see the next video.
OK, who else cannot look at a 928 without thinking of Risky Business? Must be a generational thing.
Which one of you is the U boat commander...😅
Holly S. Your better off splitting the atom. You gotta love puzzles.
Hey Ivan my wife is sitting beside me as I'm watching your video she asked for you to explain the BINGO wiring made me laugh
That's more like an electrical schematic then a wiring diagram. I feel your pain as an electronics technician myself. The multicolored pens are the best way to track the circuit besides redrawing it yourself for the affected circuit.
A list of common Bosch terminal designations also help in diagnosing European vehicles. I've had to go though some thing similar with Mercedes Unimogs.
The complexity of this headlight electrical system is why we have computers. For all of the anti-computer people....
"The quality goes in before the name goes on." Ohhh ... wait, that was Zenith. 🤣
Nice work as always I´m surprised you put silicone grease on the outside of the rubber boot. It will collect dirt. Better off inside the boot
A company I used to work for had massive posters on the shop wall for the trucks. The electrical schematic was about 5 feet by 5 feet but had everything on one page for the entire truck.
My god you make some sort of complicated game out of this wiring diagram nightmare good luck Ivan cheers
Love the street toe sandals
Ivan I would get in touch with a friend and instructor of mine across the pond who is very sharp on these over the top cars. Check him out at Mechanic Mindset Darrin Quinn. Great guy and even mention my name if nothing else he probably get you a better schematic. Good luck Artie 👍 Ivan is the NPN transistor any good. Do you. Have all 3 signals. Base collector and emitter. Just maybe you never know 😊
Earlier in the video you mention how you like older cars without modules, the schematic you worked on is what the circuitry is doing in the modules that go unseen today.😅
Great videos as always Ivan. We have a 2007 GMC Yukon with stabilitrac issues that have left us brain damaged, LOL.
The diagram seems reasonably easy to read that being said my thought would be to find the resistors specs & try to replace /build a new one.( I come from a telecommunications background which makes the diagram easy for me to compute & I also used to build computers so maybe that helps me understand this dilema) Cheers maybe this will help with the solution oh & if that resistor can't be acessed build one to attach to the old relay case.Good luck mate nice to see you.
Thank you PHAD , always appreciate your diagnostic videos. Your one of the best out here.
Cool old school. I've got a 85 Z28 in the garage that hasn't been run in decades and needs a thorough going through...one of these days...
Welcome to Euroland way of doing things! I used to think one engineer had a terrible nightmare and this was what the engineer saw! Hey! It worked in the nightmare, why not in the car.
I'm glad we never had Euro vehicles in the City Fleet.
You have to draw your own schematic/diagram on separate paper in the position to indicate the lights would be in the on position. You could also reverse engineer the circuit from the bulbs back writing out the circuit as you went along. Energizing the circuit at the bulbs and backtracking is another way.
All this AFTER testing the fuses. And those bullet fuses are known to look good but can have intermittent connection with the holder. Sometimes just rotating the fuse was enough.
Good one Ivan!
The diagram is different but you made it understandable. Great job, thank you for posting this. 😊Steve
Great video Ivan! I have worked on some machinery from Europe. Wiring diagrams are not the easiest to follow. Even when the equipment was only 10 years old some electrical parts were hard to come by or discontinued / not available. Good luck finding anything in the US for that car. I had to order used parts from Europe to get the parts I needed. lol
You These plans are not complicated !
These are Siemens standard plans, these were the "good and legible" system 20 years ago and many, many systems, also in the large area over several control cabinets, are still drawn in this way today. If you work with it for a longer time, you quickly see interactions between subsystems and the like. With digital CAD and the electronic documents, it is of course easier to show only a part of the area like LIGHT, but sometimes you have also to follow the plan over several pages (or scroll) in your digital plans.
It's the same as with troubleshooting, there are also several systems there, e.g. Dutch/British: A switch doesn't work and the next thing you look at is the switch itself, then the line in front of it / German system: switch doesn't work and the next thing you look at whether the main power supply of the house is there (230V/120V)
Have you checked for a ground on that transistor relay? That transistor will need power which you know you have and a signal to trigger it which you also know you have... but in order for the transistor to work, you will need a low potential somewhere coming into the relay.
Don't know why you spent so much time researching the pop-up headlight motor. That section is working. I realize figuring out how the Combination Light Relay works was necessary. I would've started at the headlights and traced/tracked the circuit(s) backwards to find where power to the headlights was lost.
Go to love the Ze Germans and their wonderful engineering. Props to you for taking the time to figure it out! Poor customer paying the diag fees lol
No hate I live your video's 😊, I rather see a longer episode than different parts.
Just my opinion again love the channel 😊
I had a multipin relay like that on my 85 300d.
That was over twenty years ago and so I cannot remember exactly what it controled. I think it was the a/c.
Anyway, I used a paper clip to jump some of the plug holes after I figured out which ones to jump and that was after I traced the problem to that relay. No diagrams!
I did manage to get a new relay eventually. Problem solved. 😂😅
I heard somewhere these were dogs with that 3 speed automatic like most auto gear boxes of that era. The manual ones were much better. Is that an automatic or manual?
5 speed manual. If it was auto, that would be a crime haha
Those diagrams were common in europe in the past , I have repaired many a photocopier using diagrams like that, you do get used to them if you use them a lot. On your other comment about over complicated engineering, I have said on your site before that it has always been the case with VAG which makes them expensive to repair. Unfortunately their marketing dept has done a good job on the younger generation in the UK and they think there the greast thing since sliced bread.
Major head banger, Ivan! German schematics, particularly from the 70s and 80s (from then on, they started using blackboxes), apear to have been drawn by complication-obsessed engineers - why use a relay, when you can use a dozen of non-standard parts... I would guess you have a coil wire broken by vibration, inside the overcomplicated relay - if it's an outside turn in the coil and you can open the housing, you should be able to salvage it.