So the 1995 Max is now blowing a P0600. I have searched high and low on here, and it seems this isn't too common but not too rare.

So I'm in the manuals, stickies, and old posts, and looking to see what it could be, and it really looks like its probably harness, otherwise its the TCM or ECM.

My question, has anyone actually done the investigation and run across anything else I should check. There are tons of posts with questions but not a lot of helpful hints on this one. Never messes with the TCM before so not sure how long it should last...

 

Do you have any problems with your speedometer? I used to get P0600 along with P0500 (vehicle speed sensor), and they always correlated with intermittent speedometer failure. After I swapped out the printed circuit board on the back of the instrument cluster, I stopped getting both codes. Sometimes, it would set only P0600, but I think now it was a spurious code.

It's hard for me to imagine how the wiring between the PCM and the TCM could develop a fault, unless the car's been wrecked, or had something spilled through the dash vents. So I didn't see the point of trying to check the connections.

 

My speedo works fine. The odometer has been broken for about a decade so doubt that's it.

I did notice recently that it seems like my car isn't shifting as smoothly as usual, i was trying to attribute it to cold weather (???) but when this code came up, it actually makes me think I have transmission trouble-a-brewing and this code is just the tip. I hope I'm wrong.

 

I used to have P0600 along with KS and an O2 codes......After putting new KS and O2 sensor ,P0600 didn't come back