Thread: L67 DTC P1671 from 99 Grand Prix

Hey everyone, I'm new to the site and researching a DTC code. Have any of you had any experience what the P1671 code means? I have been able to find that it is for driver 4 line 1 with my online search but no definitive answer as to what that pertains to. I also found it could be a bad Check Engine Light Circuit, bad PCM or bad wiring (PCM circuit wiring section 71). Thanks so much for any input on where to go from here!

EDIT - What started my research was the engine suddenly dying after a short period and being unable to start, this code appeared in the ODBII readout. Thanks again!

P1671 MIL Control Circuit Malfunction - With Automatic Transmission

sounds like there is a problem with your mil light circuit I would start testing some connections if the bulb is working if not then i am guessing it is a burnt out bulb

also check fuse 12 in the under hood fuse panel as it relates to that circuit

This can also be caused by a bad pcm so if you have changed it recently or have a spare to swap and try than you could do that.

My car threw the same code the minute I swapped out my PCM...never had any problems though...

fst4dr, thats great info...hours of searching didnt even find that for me.

Thanks for that, that is great info. Since the lamp in the dash is illuminating I'll take a guess that it is the PCM, since this issue with it randomly shutting off has been around for a bit but not consistently like it is now, all fuses look good, and all the wiring seems to be secure with no corrosion or breaks. I appreciate your help!

not a problem of course it was pretty easy for me but that's part of having access to tech resources