Causes and Fixes U0100 Code: Lost Communication with ECM/PCM

How to fix a U0100 engine code: Lost Communication with ECM/PCM
Test OBDII Port Video: • Fixes OBDII Scan Tool ...
A U0100 means that the vehicle CAN Bus can’t communicate with the engine control module (ECM), power-train control (PCM), module transmission control module (TCM), or other computer modules.
The CAN (Controller Area Network) is a protocol that allows the ECM, PCM, TCM and other modules to communicate with each other.
Diagnosing a U0100 can be difficult and time-consuming.
Possible Causes of the U0100 Code
Issues with Alternator Charging or Battery
Blown Fuse (Check OBDII Port Has Power)
Wiring Harness Open or Short
Wiring Harness Has Bad Ground
Faulty ECM TCM PCM
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[@luissoco]

I wish all videos were like this one. Thanks buddy!

[@naptown4200]

Thanks bub, couldn said that no better straight to the point 👍🏽

[@God_is_good_]

Jesus loves you, God Bless✝️

[@God_is_good_]

Jesus loves you, God Bless✝️

[@BrandonSpicer-wl5fy]

Amen

[@JasonStephens-o1m]

What would cause the CPM not to communicate in a 07 Ford fusion code reader sides no communication

[@riversidesagkeeng30]

The fuse box your using in this video. Is it a 2021 GMC canyon?

[@somluckphommanichanh8336]

Thank you sir

[@age_of_reason]

I have a 2015 Nissan Versa Note that was throwing a P0138 (Bank 1 Sensor
2 High Voltage) and check engine light. The exhaust system was old,
rusted and leaking everywhere. I replace the entire exhaust system
(intake manifold back) except I didn't replace the o2 sensors (yeah
pretty dumb I know) and the P0138 & CE light did not go away. With
the new exhaust system, I tested the downstream o2 sensor and got poor
readings (showing it was bad), so I replaced it and the P0138 code went
away. But after testing the old o2 sensor/wiring & replacing the o2
sensor, the car wouldn't start (it turned over but would not fire up). I
found a blown 20A fuse marked 'ECM' in the engine compartment fuse box
(next to the battery), replaced it and the car fired right up, but it
still shows CE light and U0100. The car runs fine so what could be
causing the U0100 code?

[@JasonStephens-o1m]

What would make a 07 Ford fusion loose communication code reader sides no communication

[@gtavlovers3354]

Hey buddy, I got a 2018 f350 6.7 diesel and it says in the dash, ENGINE COOLANT OVERTEMPERATURE" I haven't started the truck for like 3 weeks and is saying that., Now it doesn't start anymore, I got that message in the dash and I also got the U0100 and U0101 Lost communication with ECM/PCM "A" it has new batteries but the truck is not cranking and not starting.

[@Kjwheels]

Thanks 🙏🏾

[@seth3209]

Mine?… 09 Outlook U0100… after watching this! I pried my ECM Open and found 2 Major Capacitors burnt up! On an aftermarket website… $111. W/ no core charge

[@ralphwhitaker8761]

Was it already programmed

[@telikofreedman2376]

I took my Sienna to the dealership, because of the trac off and engine light showing up. OBD2 said lost connection to TCM, and ECM/PCM A.
Dealership told me it would cost 24000 USD to take out the harness and replace it.
Obviously didnt pay that.

[@joegamer1696]

can this error code blow engine fuse and not start engine??

[@tyrinp6882]

Please help….Toyota Fortuner 3.0d4d ….hard start with a diesel knock, tried new injectors, new diesel pump….U0100, U01023/24 codes

[@dannyclubb4309]

I'll also have a P0700 transmission code . All of this started after my throttle body was giving me issues and changed it. . New battery and alternator so the voltage is good

[@luker.6967]

Thanks! Now to find the problem on my 2010 Mazda 3 :((((

[@christophermanning1610]

My car acted like it was an EBCM problem but when I ran a diagnostic it came up with the U0100 code. Could a bad communication problem from the ECM cause that scenario where the EBCM isn't functioning properly?

[@HVAC_Mechanic]

There may be an issue with the wiring (CAN Bus) that can cause multiple problems depending which wires are damaged.

[@skpathan779]

No Ball
Free Hit

[@dannyclubb4309]

I will randomly get this code because my Dodge Charger will die when at idle or at a stoplight.

[@MrHereWeGoYo]

Dealing with this now. 2015 Charger R/T w/100k on the clock. Was just plodding along when the car sputtered and died. At the shop today they found codes U0100 and P1DF3. "Take it to the dealer." They don't want any part of it.

[@JasonStephens-o1m]

What would make a 07 Ford fusion loose communication code reader sides no communication