2009 dodge challenger rt with 5.7 engine no crank, no start and no communication

That's how I hooked it up. I'd hook it again with the black lead to battery negative.

I'm going off these diagrams.

Here's some waveforms I pulled at the can lines on the pcm and tipm sides.

From my understanding, the TIPM acts as a gateway between CAN B and CAN C. If you are using a scanner that can read all the modules in the car, you should at least be able to communicate on the CAN B if the TIPM is working as designed.

Yeah, If i use obdlink, the can b bus is accessible but not the can c bus. Get a U0001 can c bus error.

I've gone through the wiring but don't see any other damage. The rebuilt PCM I tried has some corrosion on the pins. Not sure if it's also not working but the rebuilding is going to send another unit. There was or still is a rodent running around in the car. Not sure if there is some unseen wiring damage. But tried using the powerprobe short finder but didn't find anything.

The dlc power and grounds check out okay and the can connectors have 2.5v and 60ohm across.

I believe the 60 ohm reading you took was of the TIPM, and not the CAN-C. Check for 60 ohms at the CAN-C connector at the TIPM, not the DLC. The 2 terminating resistors are in the PCM and WIN.

You can experiment if this assertion is true or not. Measure across the DLC for 60 ohms. Then unplug the PCM or WIN, whichever is easier to get to. The DLC resistance reading of 60 ohms should change. Does it?

 

Remember to disconnect the battery for resistance testing.

ChallengerDude wrote:

Yeah, If i use obdlink, the can b bus is accessible but not the can c bus. Get a U0001 can c bus error.

I've gone through the wiring but don't see any other damage. The rebuilt PCM I tried has some corrosion on the pins. Not sure if it's also not working but the rebuilding is going to send another unit. There was or still is a rodent running around in the car. Not sure if there is some unseen wiring damage. But tried using the powerprobe short finder but didn't find anything.

In my opinion, If the pcm were the cause of the  CAN C bus error, you would most likely have a lot of echoes on the CAN lines  if the terminating resistance were missing unless the terminating resistance were fine, but the transceiver were bad. When you unplugged the pcm for can lines testing, you would have the communication back as it would be the reason that the bus were down. The pictures you posted  did not  show echoes. The quality of the pictures were in part due to the scope itself.

 

The can bus lines at the TIPM measure 60ohms. The DLC shows 62ohms and no change with the PCM and WIN unplugged. The battery was disconnected.

The can bus lines at the TIPM measure 60ohms. The DLC shows 62ohms and no change with the PCM and WIN unplugged. The battery was disconnected.

That's great information, thanks for testing that.

For can high look for bias voltage of 2.5V and the signals jumping up to 3.5V. The first picture is obviously can high.

The second picture where I put question marks. Did the bias voltage drop down to 1.5V from 2.5V ?
The question marks I drew, I think that's image ghosting because of how fast the signal is going across the screen.

What does can low look like. It should be biased around 2.5V and signals should drop down to 1.5V.

You need to stare at these to find any abnormalities.

 

If i use obdlink, the can b bus is accessible

Can the steering Control module talk to CAN C ? Or rather, is it throwing a lost com to pcm?

It's on CAN-C and CAN-B.

 

I am curious to see what will happen if you start bypassing all the modules on the CAN C. Starting from the DLC to pins 5 and 6 (where the CAN lines exit the TIPM) to the IN and OUT of all the other modules. If there is a bad wire or module, you should regain communication.

That video is a great resource. Yeah, 2 pcms being bad is unlikely. Just guessing since the replacement one was rebuilt and has some corrosion on some of the pins. Wiring seems to be okay. Maybe just start unplugging more modules to try to eliminate the problem and at least be able to talk to the pcm.

I can access can b but there's not option for the steering column module.

By bypass, do you mean ubplug the module or cut the can wires?

I've unplugged some of the easy ones so far. ABS, TPM and shift modules.

Here's what can low at the pcm looks like.

So the cluster shows an etc light and cel. It also shows an abs light when I unplug the abs module. Since the cluster is on can b, that would mean that first the pcm is working well enough to communicate through the tipm and send the etc error. But can't communicate through the tipm to the dlc. Would the tipm be causing the issue with the dlc not communicating with anything on the can c?

I checked powers and grounds on the etc connector before but could check it with the scope.

By bypassing, I mean to isolate each module. The tipm has 2 can c lines going into it and 2 coming out of it. You remove the tipm and find 2 wires , then use the 2 wires to complete the can c lines. Do the same thing to the other modules and see if you get the communication back
The way that Bernie was showing in the video 

So jump the can high and low while still leaving the module plugged in.

I did try jumping the 2 sensor wires for the etc after seeing that at the pcm they had 4v and 0v and at the etc they had 4v and .8v. But the connection at the pcm may not have been good with the back probe.

Remove the module and complete the can lines with the jumpers
(Jump the can lines with the 2 wires)
Iwith an open etc wire  you should have 5v at the pcm , not 4 Check again  to make sure