I need some help. I have no gauges on my dash except for my tack that works. I have put a new transmission wiring repair kit, I have cleaned all the terminals, I have checked all the wires that I can see and I put a new pcm on it. it will crank and drive but i have to start off in first and to get it started going then I can put it in drive and it will shift on its own. Im about ready to drive it off a cliff. (lol) any suggestions will be much appreciated and at this point I'm willing to try anything. 

 

@Mopar1973Man , do you think you could try to help this guy? He's gotten no response for 6 hrs. Anyhow he has no working gauges except the tac and I know the trans is controlled by the PCM, could these two symptoms be related ? If not, what about a bad speed sensor in the trans ? Any other sensors that might be the culprit? Lets try to help as we all know what that's like to be stuck.  Shot in the dark... A bad connection or pin on the PCM . Many thoughts come to mind like crank sensor, shifting cable adjustment, APPS. Anyone?

 

Prayers from Oregon that you find it and is a simple fix.. We lost our prayers emoticon... what's with that?

Yeah I would check power and grounds of the PCM. Then I would pull the PCM and send it to Auto Computer Specialist being the PCM creates the CCD network and supplies gauge data. Cluster is what creates the Bias Voltage for the CCD so it won't hurt to test the cluster by holding the trip button turn the key on and watch for CHEC to show and release. Any codes please list them.

the pcm is brand new.  the codes are 920,921,999.

 

I also put a new APPS

 

Again I would still check the flash on the PCm to be sure the PCM is programmed correctly...

Edited February 9, 20232 yr by Mopar1973Man

Where do I buy one of those scan tools? Does it have to be that particular one?

The pcm i just got back yestereday. it supposed to be good. set to my vin

4 minutes ago, Just another 01 said:

Where do I buy one of those scan tools?

Anywhere really the favorite I like is the OBDLink MX series. 

https://www.obdlink.com/products/obdlink-mxp/

 

Then you can monitor live data and also read error codes with your cell phone or mobile device. 

So, lets just say there is no message and or no pulse, then what?

Again back to the PCM and verify the software on the PCM is correct. PCM is what creates the CCD network bus. Then the gauge cluster sets the CCD Network voltage to 2.49 and 2.51 volts. Which you can measure at the OBDII port with a DVM but make sure to wait several minutes for all modules to stop talking. 

 

So I have a launch scan tool, why doesn’t any of my transmission data read?  It has a place for a reading but there is lousy a line there, no reading. Also my overdrive button on my column shifter doesn’t work. I’m driving the truck right now and it shifts fine. 

I ordered the OBD2. It will be here tomorrow. 

My Launch 123 will not read theses transmissions either but my Snap-On Ethos+ will read all kinds of data about the transmission.