No Communication With TCM

KaMiKaZi_t0M · Post by **KaMiKaZi_t0M** » 25 Jun 2013, 06:37

So I put a rebuilt ABS module in (we had one in stock) and it did not help. One additional bit of info I have found is the positive battery cable gets screaming hot when the car is running. Not sure if that is common or could possibly be a contributing factor. I figure the more info I give the better chance of me solving this...

Post by **abscate** » 25 Jun 2013, 13:50

As Tom & Ray say, Ten yard penalty for witholding information...

If its too hot to touch, you need to deal with that first. That kind of current is sure to be pulling battery voltage all over the place, not to mention a fire hazard.

Open ground or something shorting to ground - find it before proceeding.

Post by **precopster** » 25 Jun 2013, 15:17

Corrosion inside the sheathing on the cables is most likely causing voltage drop and lots of it. If there were a short the OP would be dealing with a battery flattening deal every couple of days. Still wouldn't hurt to measure current draw with ammeter from + battery terminal to red cable. Should be no more than 50mA with key OFF

It's more likely this is only for the first inch or so after terminals. It's characterised by white powdery looking copper. Get slicing with a utility knife and have a good look.

B+ cable going to the alternator gets equally affected.

KaMiKaZi_t0M · Post by **KaMiKaZi_t0M** » 29 Jun 2013, 10:20

Here's some updates. I tried swapping the speed sensors (on the trans), no help there. Here's some more info, my scan tool is informing me I can't get the torque converter to lock, and ordinarily I can force the solenoids to lock; and they will not. Also, if I rev the engine over 3 grand the flashing stops, once the revs drop it starts flashing again. Drove the car 2 miles, still NO codes.
Tom

nzvlnr · Post by **nzvlnr** » 11 Jun 2014, 21:00

Did you ever solve this problem? I have my car at an Indie shop and they have had it for a month...flashing arrow...drives ok...just flashing arrow.....I had my TCM and ECM both sent to xemodex and there was nothing wrong with them. I even ordered a used one ..popped it in and nothing.....
Originally the indie shop said the communication with the TCM isnt working, thats why I sent them to xemodex. I have not been able to use this car for all of 2014....I bought an R...luv it but this is my commuter and I need it back...HELP!!! Do you remember me Mattymoo...you sent me an abs unit and I sent it back...it didnt help...
I dont want to scrap this car...it has new rims, HD bilsteins, timing belt water pump...I could go on and on...

Post by **Matty Moo** » 12 Jun 2014, 06:12

You need to take it somewhere else. Somebody will figure out what is wrong with it, and it's probably something simple.

nzvlnr · Post by **nzvlnr** » 06 Jul 2014, 19:11

The issue was the PNP switch. He said he has never seen a car behave like this with a bad PNP switch. He put a used one in and drove it for a couple days, all problems alleviated. He ordered a new one and installed it,.,...car runs like a dream....; - )

No Communication With TCM

Re: No Communication With TCM