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2012 ram 1500 4.7L electrical problem

Asked by: 24 views Electric Question

2012 ram 1500 4.7L electrical problem

I recently changed out my evaporator and when I after I have put everything together I went to connect the brake light harness on the mount by the brake pedal, my service 4wd light, my abs, my brake and traction control lights came in. I shut the truck off and they all disappeared when I turned it back on. When I went to mount the brake light harness back on the mount by the pedal, it cause a short, making the engine run horrible and all those same lights came back on. I shut the truck off but when I try to turn it back on, it will crank just won’t turn over. I have checked the fuse box and all relays have everything working except the 2 for the brake lights on both passenger and driver side. I have also plugged a scanner tool in and it has gave me code P0882. My question is what could it possibly be and where else to look and how to fix this problem. Thanks again


7 Answers

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    A Faulty brake pedal sensor can put the engine in limp mode and probably that’s why the engine ran bad.

    P0882 is low voltage / short to transmission control module.

    In what system did you find the P0882 code? What happens if you clear the memory? Is the trouble code coming back?

    Check trouble codes in the systems
    Engine control unit
    Transmission control unit ( If possible )
    Brake control unit

    P0882 is often caused by a low voltage to the TCM

    The fault sounds like a burned fuse yes. Check the voltage on each fuse in the fusebox/s to make sure that they’re functional


    Ask A Mechanic Admin - Mar 28, 2018 |Reply

  2. 0 Votes Thumb up 0 Votes Thumb down 0 Votes

    The scanner I have used doesn’t show where the code came from. Is there a way to test both the TCM and ECU. I have disconnected the terminals from the battery and the lights have came back on and wont run at all. And when I do check the fuses, what’s the voltage that they should typically have? Is there also a way to test the relays as well?

    David0917 - Mar 28, 2018 |Reply

  3. 0 Votes Thumb up 0 Votes Thumb down 0 Votes

    Yes, that’s because you used a generic DTC reader.
    In this case, I would try to read the transmission control unit with a DTC reader that can do the job, if you cant get communication with it, there should be a Power 12volt problem to it or a damaged transmission control unit

    When you measure the fuses, ignition on and you should read either 0 Volt – 0 volt or 12 volt – 12 volt on each side of the fuse. If you have 12 volt on one side and 0v on the another, the fuse is gone.

    Check relays is a bit tricky, depending on what kind of relay it is and they do not often get damaged.

    Ask A Mechanic Admin - Mar 28, 2018 |Reply

  4. 0 Votes Thumb up 0 Votes Thumb down 0 Votes

    is there a certain DTC reader you would recommend? Or what kind to look for?

    David0917 - Mar 28, 2018 |Reply

  5. 0 Votes Thumb up 0 Votes Thumb down 0 Votes

    The most cheaper DTC readers can only read the generic DTC memory and you will get the generic trouble codes from the engine DTC memory. To get manufacturer codes & codes from other control units you have to get some more expensive dtc reader.

    Do you have access to a small workshop that could read the DTC memory for you?

    The DTC tool I use at my job costs 50.000 $~ , so of course, there is a difference!

    Launch CRP123 OBD2 Scanner ABS SRS Transmission and Engine Code Link to Amazon
    A tool like this would probably work, but have to make a bit of more research to make sure it works with your model.

    If you want to check for one yourself, you have to check that they can read more than only the engine control module and are compatible with your model.

    Ask A Mechanic Admin - Mar 28, 2018 |Reply

  6. 0 Votes Thumb up 0 Votes Thumb down 0 Votes

    Sadly not around me but I did plan on getting a new dtc reader sometime tomorrow or Friday along with a few other things as well.

    David0917 - Mar 29, 2018 |Reply

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    So an update. I have found a few fuses that are under 12 volts and one of the relays (k5 for the pcm was warm when I touched it) I’m just waiting on my scanner tomorrow to see where the code is coming from exactly.

    David0917 - Mar 30, 2018 |Reply

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