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P1878 Diagnostic Code

fiftford

New member
My 1997 Grand Prix has a P1878 Trouble Code. I searched the forums and couldn't find any information other than the description P1878 Transmission Transfer Case Disengaged Solenoid Circuit Failure. Does anyone have any suggestions how to test or repair? Thanks
 


Fairly certain. I wrote it down but then cleared the code with my scan tool. It just reads and clears codes though. No diagnostics. I'll drive it a bit and see if it comes back.
 
Seems very odd.. are you positive about the code number?

It took a while but the code came back on and I did have the code number wrong. The code is p1870, which is for transmission slipping. I checked the fluid and it was a little over a pint low and did not smell burnt. My son has been driving the car and said it was shifting "a little funny". I topped off the fluid and I'll drive it tomorrow. But... is there any chance that the low fluid triggered the light, or am I most likely looking at valve body issues? From what I heard I think the trans has to be removed from the car to remove the valve body. The car has around 185k on it now so I'm not sure it's worth an expensive repair bill. I do all my own engine and suspension work but am not comfortable with the transmission rebuild. Any advice?
 
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