Engine/Transmission (1998.5 - 2002) 3 Intermittent Transmission Codes

[Allnew2Me]

I have 3 intermittent transmission codes that are only set upon a cold start. They put the transmission into limp mode until cleared.



PO743 Torque Convertor circuit electrical

PO753 Shift solenoid A circuit electrical

P1765 Manufacturer control transmission



If I clear them when I start the truck they will not return on any other start the same day. If, when I start the truck cold I just go straight to start and do not let the key rest in the on position, the codes will not set at all.



Is this just a simple solenoid issue? I have a spare solenoid assembly and also a pressure transducer but would like to only change what is causing the problem. Thanks

 

[JLandry]

These trouble codes can all be set by a faulty Transmission Control Relay which is located in the Power Distribution Center (located under the hood on the driver's side fender). The relay should be labeled "TRANS. " Try swapping out this relay for another non-essential relay of the same footprint... such as the wiper or horn relay. If the problem disappears, well you've found the source and can replace the defective relay. This relay is common and should be available at any auto parts store.



If swapping out the relay doesn't solve the problem, post here again and I'll list the specific trouble shooting steps you'll need to pinpoint the cause.



Good luck,



John L.

 

[Allnew2Me]

Thanks for the tip John, I will try the relay swap and see if that does anything for the better. I will post when I have the results.

 

[Allnew2Me]

I swapped out the relays as you suggested but no change. The same three codes appear in the same manner as before.

 

[JLandry]

I swapped out the relays as you suggested but no change. The same three codes appear in the same manner as before.

Bummer!



I'll post trouble shooting steps tomorrow. Gotta run right now.



Regards,



John L.

 

[JLandry]

I've uploaded the relevant pages from the Dodge Diagnostic Procedures manual for the trouble codes you've been getting. If you don't have a DRBIII scan tool mentioned, just substitute your favorite code reader or a multimeter as needed.



Good luck,



John L.

 

[Allnew2Me]

Thanks again John for the point in the right direction. I will go through these procedures when I get a chance. It looks like a little time to go though all the steps. I am wondering if perhaps my Banks brake controller, which is tied into the PCM could possibly be causing this trouble.

I don't have a DRB but do have a VOM and a scanner.

 

[Allnew2Me]

So far I have verified that the relay is okay by your 1765 tests. I am still working on the PCM connector tests and the others.

 

[Allnew2Me]

After finally getting around to going through all the diagnostics that John was so helpful in sharing with me I have deternmined that the Banks brake controller is indeed at fault. If I remove the controller from the PCM circuit by running the torque convertor lockup control wire Orange/Black directly to the transmission and not through the brake controller eveything works fine and no codes. As soon as I place the controller back in the circuit it throws codes again. What I don't understand is why it only sets a code upon first start and not any other time that day when starting again. Anyway, I have resolved the issue and will send the controller back to Banks to have them take a look at it.

Thanks John for the help.