2007 Chevrolet Malibu P1818

KRISTINAWHITE09

MEMBER
2007 CHEVROLET MALIBU
3.5L
6 CYL
FWD
AUTOMATIC
161,000 MILES

Periodically my car will have a DTC of P1818. I'm not having any issues with the car actually being in reverse when it's in park or rolling away. The only issue I'm having is with the doors not automatically locking/unlocking when I put the car in park/reverse. Also, on the dash where it highlights whether you're in park, reverse, neutral, etc, it's not lit up. I recently had a new TCM put in my car and the dealership programmed it. Could this be an issue with the programming? I know there was a TSB about it but my car wouldn't qualify for it. When I clear the code, it goes back to normal, then randomly stops working.

Tuesday, August 5th, 2014 AT 6:12 PM

4 Replies

FREEMBA

MECHANIC
1,152 POSTS

P1818 = Transmission fluid Pressure Valve Position Switch Indicates Drive without Drive Ratio.

Have you had any work done to the vehicle where the electrical connection to the transmission had been disconnected and the ignition key turned on? If so, this will cause the code you have.

Make sure that the electrical connection to the transmission is well connected.

To trace this code further you will have to have a technician connect a scan tool to your vehicle and trace the problem step-by-step.

Was this

answer

helpful?

Yes

No

+1

Tuesday, August 5th, 2014 AT 6:52 PM

KRISTINAWHITE09

MEMBER
44 POSTS

I recently had a TCM put in and programmed. Also had an electrical issue with a wire that goes to my TCM. They put in a new wire and connected it at the fuse box. I'm getting a new fuse box put in as soon as I get the part, so I'll have them take a look at it then. I had this issue before I had everything replace though, and had someone look at it. When they cleared the code, the problem went away but came back after a couple weeks. The TCM was programmed by the dealership. I've asked them to look at the programming again but they're going to charge another $100.

Was this

answer

helpful?

Yes

No

+1

Wednesday, August 6th, 2014 AT 5:03 AM

KRISTINAWHITE09

MEMBER
44 POSTS

I was just told by the dealership that if I have an issue with my fuse box, it could be causing voltage fluctuations to the TCM wire I just had replaced (the mechanic grounded it near my fuse box). This could apparently be causing the false code my TCM is throwing. I have an issue with O2 sensor DTC's right now and was told I need a new fuse box because there's no voltage to (at least) the O2 sensor circuits. I guess I'll have the fuse box fixed first, clear the codes and see if the P1818 comes back.

Was this

answer

helpful?

Yes

No

+2

Thursday, August 7th, 2014 AT 6:41 AM

FREEMBA