I was just thinking, couldn't you use the output of the factory relay as the sense wire for the universal relay. This way it would keep the heat off of the factory relay and the power would go to the new relay.
That fan relay brain is the problem. Not to mention the hassle of digging it out (unless you cut a hole in head light bucket liner to get to it). I got a simple digital thermostatic switch and a solid state relay ($10 total) and now the temperature activated switch throws battery voltage through the SSR right to the fans. I took the ECU and the stupid fan controller out of the loop entirely for $10 bucks. A Bosch-style relay would probably work but they make me nervous when they are always on with a big current draw.
@@chadhalsted604 I could but when a digital thermostatically controlled switch is $2, I put in the thermo-switch. I put the whole rig in a water-proof box and it lives happily next to the battery. I cut the end off the fan wiring connector and spliced straight into it. Easy.
@@SuperSharpBlue Why would it? I'm legitimately asking as I don't know why cutting the fan relay out of the controlling the fan would cause the ECU to light a trouble code? Mine never did as long as I had it but I sold the Jeep. New owner never got back to me to complain that the CEL was on for a fan relay or anything else. As far as the Jeep knew the relay brain-box was still controlling the fan but it wasn't.
Im confused. I have a 2000 Grand Cherokee 4.0 same wiring for fan. Here is where i get confused. you talk about the voltage going to the fan . checking the voltage on my wiring, here is the difference. Gray wire: has the 40 amp fuse the wire is always hot from the battery 12vlots Green wire: Brings battery voltage to the fan. Dark blue/pink: relay control (from PCM ) black wire: ground to fan. Now then to test : 1. Check Gray wire for battery power. No power possible bad fuse. 2. Jumper gray wire to green wire, fan should run 3. Check black wire for good ground 4. Ground Dark Blue/Pink wire TO ENGAGE RELAY and the fan should run. Is this what you found also Larry S.
I had the same problem ran it on a switch for a year or so, then I bought a kit that had a thermostat that you stick through the radiator that you attach to your signal wire
excelente video, estou com esse problema aqui no brasil, o que fis foi puxar o positivo que aciona o rele da do compressor, ao ligar o ar condicionado a ventuinha liga, mas liga ja no maximo, isso nao e arriscado?
I was just thinking, couldn't you use the output of the factory relay as the sense wire for the universal relay. This way it would keep the heat off of the factory relay and the power would go to the new relay.
Did the Heat Sink work?
That fan relay brain is the problem. Not to mention the hassle of digging it out (unless you cut a hole in head light bucket liner to get to it). I got a simple digital thermostatic switch and a solid state relay ($10 total) and now the temperature activated switch throws battery voltage through the SSR right to the fans. I took the ECU and the stupid fan controller out of the loop entirely for $10 bucks. A Bosch-style relay would probably work but they make me nervous when they are always on with a big current draw.
could you run the control wire, that turns on the A/C compressor, to a SSR and make the e-fan kick on whenever the AC is on?
@@chadhalsted604 I could but when a digital thermostatically controlled switch is $2, I put in the thermo-switch. I put the whole rig in a water-proof box and it lives happily next to the battery. I cut the end off the fan wiring connector and spliced straight into it. Easy.
Sounds like the ultimate solution. Would be great to see how you accomplished that with a YT video and a parts list!
Does the check engine light not come on?
@@SuperSharpBlue Why would it? I'm legitimately asking as I don't know why cutting the fan relay out of the controlling the fan would cause the ECU to light a trouble code? Mine never did as long as I had it but I sold the Jeep. New owner never got back to me to complain that the CEL was on for a fan relay or anything else. As far as the Jeep knew the relay brain-box was still controlling the fan but it wasn't.
Im confused. I have a 2000 Grand Cherokee 4.0 same wiring for fan. Here is where i get confused. you talk about the voltage going to the fan . checking the voltage on my wiring, here is the difference.
Gray wire: has the 40 amp fuse the wire is always hot from the battery 12vlots
Green wire: Brings battery voltage to the fan.
Dark blue/pink: relay control (from PCM )
black wire: ground to fan.
Now then to test :
1. Check Gray wire for battery power. No power possible bad fuse.
2. Jumper gray wire to green wire, fan should run
3. Check black wire for good ground
4. Ground Dark Blue/Pink wire TO ENGAGE RELAY and the fan should run.
Is this what you found also
Larry S.
I had the same problem ran it on a switch for a year or so, then I bought a kit that had a thermostat that you stick through the radiator that you attach to your signal wire
excelente video, estou com esse problema aqui no brasil, o que fis foi puxar o positivo que aciona o rele da do compressor, ao ligar o ar condicionado a ventuinha liga, mas liga ja no maximo, isso nao e arriscado?
Note: this relay is a negative trigger not a positive
What’s that part number ?
Wheres Part 2??