P2122 codes

Ftknox1301 · Post by **Ftknox1301** » 06 Jan 2020, 19:36

Greetings everyone. The other day my wife's a 01 XC70 broke a serpentine belt, she was able to drive the car to a safe location and of course eventually everything shut off on her from running on just the battery. I replaced the belt and took the car out for a test drive only to find out it would only go up to about 30 miles per hour. I pulled the trouble codes (OBD2 scanner, don't own Vida/Dice) and got P2122 and P2121 codes. From the research I have seen this can be related to either of the throttle body or the accelerator pedal, any advice on this issue would be greatly appreciated. Thank you.

Post by **SuperHerman** » 06 Jan 2020, 20:08

My sister's 2002 XC70 suffered similar codes and drive problems - after replacing the pedal with no change the diagnostic tree suggested a relay may be the cause. I was not there, but check your relays including those in the trunk area before you start throwing parts at it.

Hopefully the legend RickHaleParker can chime in and point you to the potential offending relay's location and part number. You might be able to swap it with another relay of the same part number for test purposes that is on the board.

Post by **RickHaleParker** » 06 Jan 2020, 22:43

Ftknox1301 wrote: 06 Jan 2020, 19:36 P2122 and P2121 codes. From the research I have seen this can be related to either of the throttle body or the accelerator pedal, any advice

Both: Accelerator pedal sensor, electrical connector or wiring (Open-circuit or short-circuit).

Post by **SuperHerman** » 07 Jan 2020, 00:58

RickHaleParker - correct and at the end of the wiring loom is most likely the possible offending relay. I gave my sister my VIDA set up along with my 2004 XC90

Post by **vtl** » 07 Jan 2020, 07:07

Clean the codes, they may have beeen recorded when the modules were shutting off because low voltage.

Also it is typical for the timing belt to jump one teeth or more when the drive belt snaps. Check the timing.

Ftknox1301 · Post by **Ftknox1301** » 07 Jan 2020, 07:10

vtl wrote: 07 Jan 2020, 07:07 Clean the codes, they may have beeen recorded when the modules were shutting off because low voltage.

Also it is typical for the timing belt to jump one teeth or more when the drive belt snaps. Check the timing.

Cleared the codes but they come back immediately without even showing a check engine light???

Post by **vtl** » 07 Jan 2020, 07:13

Ftknox1301 wrote: 07 Jan 2020, 07:10 Cleared the codes but they come back immediately without even showing a check engine light???

Looking at standard OBD-II P-codes, not Volvo-specific, you did not clear all of them: need DiCE/VIDA to do so.

Did you check fuses/relays? In VIDA it is also possible to run accelerator pedal test.

Ftknox1301 · Post by **Ftknox1301** » 07 Jan 2020, 07:43

vtl wrote: 07 Jan 2020, 07:13
Ftknox1301 wrote: 07 Jan 2020, 07:10 Cleared the codes but they come back immediately without even showing a check engine light???
Looking at standard OBD-II P-codes, not Volvo-specific, you did not clear all of them: need DiCE/VIDA to do so.

Did you check fuses/relays? In VIDA it is also possible to run accelerator pedal test.

About to start pulling relays now, waiting on my wife to get back with my 04 XC so I can use some of the relays out of it to swap with hers since I know all of mine are good. Any idea which relays may be the culprit?

Ftknox1301 · Post by **Ftknox1301** » 07 Jan 2020, 08:43

Okay so far I have swapped all relays both in the trunk as well as under the hood with no change. I have unplugged the wiring harness that goes to the throttle body cycled the key a few times then plugged it back in also with no change. What should I try next?

Post by **vtl** » 07 Jan 2020, 09:45

Get VIDA/DiCE, read the Volvo-specific codes, post here?