When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Hey guys, I have a 94 with the C68 electronic climate control. I have a code 10, UART Failure when scanning the codes set. I know it is a communication problem but my question is...between what? The head unit and the programmer or the programmer and the PCM?
The programmer talks to the CCM on the serial data bus. If there is no communication, then this will set the DTC 10. The control head communicates with the programmer on its dedicated data lines.
The head talks to the programmer to control the solenoids (vents) and fan.
The programmer talks to the PCM to control the A/C compressor on its own line.
I believe the UART you want to get at is the one in the programmer since that is the one on the serial bus. The programmer is low under the dash on drivers side (I think, have not been there yet) against the wall.
Here is a link for the programmer which might be of future assistance if you have some electronics knowledge.
The whole problem started when my compressor would not kick on. I thought it was low freon from just sitting but, I checked that and am now getting this code for UART failure. I guess it is probably the programmer having issues sending data to PCM. We'll this is horrible timing since I just got my interrior back together ! Hopefully it will be easier to get to than I think. Thank you very much for the reply and I'll try to follow the instuctions on that site and get things cleaned up!!