04 XC90 troubleshooting stuff

truss · Post by **truss** » 11 Feb 2016, 08:25

Hey Guys...GREAT INFORMATIVE SIGHT! The best I have seen so far. My story....Own a 04 XC90 2.5t I have replaced the high mileage engine. I am now at the point that engine is in and starts. Shifts into gear etc. My problems are:

1. Tranny shifts into and out of gear fine however, the dash and shifter read as car is in reverse and backup alarms sounds etc. The car is physically in park yet this problem exists

2. Intermittent accelerator. Sometimes I have it, others I don't. Bit of info on this. I have the number 8 fuse out because it is blowing the fuse when car is turned on. I have read that there is a connection between this and accelerator issues?????????

3. I had "NO oil pressure turn motor off" warning however I found the turbo hoses were very loose, I tightened them up and warning went away...Do they have to be tightened for oil pressure????

4. Codes on my car are as follows: P2121, P2122, and P0571

5. One other issue....Car has always had a warning on dash that says brake failure stop car blah blah...this has always been there...assuming the abs module to need repaired? Also, cant seem to get my service engine soon warning to go away. You guys are awesome...thx for the great info on here...Your wisdom is mucho appreciated. If I get this fixed,I might be able to move off the dog bed and back into bed with my wife. LOL.

truss · Post by **truss** » 11 Feb 2016, 15:35

some update from today.....Ac and oil pressure wires were switched....this was causing the ac/apm fuse to blow . Don't know if this fixed my throttle but so far it is working. Codes have all cleared with the exception of the dash abs code and the tranny service code. So the only major things that I need help with is solving the tranny indicator in reverse when car is in park....and the abs issue. Any thoughts from you guys...thx

Davidisnumber1 · Post by **Davidisnumber1** » 27 Mar 2016, 04:56

more then likely the position indicator switch located on the top of the transmission where the shifter linkage is connected is out of adjustment or sync to correct this verify that the shifter linkage cable is not improperly routed or incorrectly secured to the transmission then to adjust the position of the switch first loosen the screws and rotate the switch on the selector shaft checking for the lights on the dash to show correct position. another possibility is you could have damaged the connector or one of the wires in the wireing harness causing incorrect signals to be seen by the tcm. to track that down you would need to remove the jacket from the harness and use a volt meter on ohms to poke and verify continuity from the pins in the plug to at least the firewall as a starting point. I Would also like to note that the shifter position switch its self is prone to moisture getting in it and causing issues that will make you swear that gremlins messing with you.

Also MAKE SURE THE O2 Sensor wires are carefully and properly routed clear of moving parts and the plugs are properly secured to the plate at the bottom of the backside of the transmission. Failure to do so will cause the $200 apiece o2 sensors to fail and as soon as one of those fail the ecu will begin to destroy the catylitic converter from rich mixtures along with personal experience being a 10 mpg drop in fuel mileage along with overheating the turbos and eventually valve and head damage... IM PROUD OF MY CAR BECAUSE I HAVE REBUILT DAMN NEAR THE WHOLE THING BUT I HATE MY CAR FOR ALL OF THE LATE NIGHT FUN IT COST ME WITH MY WIFE IN THE LAST 2 YEARS....