ETM vs brake pedal sensor vs. accel pedal position sensor

Gubernaculum · Post by **Gubernaculum** » 06 Dec 2012, 17:08

Got my ETM light read by a local volvo shop - I have:

9520 - accel pedal position sensor
958F - accel pedal position sensor
9150 - throttle unit (ETM), potentiometer 1 faulty signal
917F - accel pedal position sensor or throttle unit
91a7 - throttle unit faulty signal (ETM?)
904d - pedal sensor fault - (IS THIS THE BRAKE SENSOR?)

Is it worth scrounging up a junkyard brake pedal position sensor and accelerator pedal position sensor before getting a Xemodex unit?

My car is a 2000 s70 glt se with 102k miles, white sticker ETM. I am getting hesitation at light-throttle acceleration (goes away when pushed to half-throttle), and hesitation when cruising at highway speed.

Post by **precopster** » 07 Dec 2012, 05:47

It's rare to have all 3 codes at the same time. 9150 or 9160 are throttle position (potentiometer) codes. I would get the pedal and brake sensors first. Beware when pulling the pedal position sensor from your booster as it will suck the O ring back in if under vacuum. Release vacuum at the booster another way and same goes for the junkyard car.

Post by **regent** » 07 Dec 2012, 09:43

Poor contact in the Engine Management supply voltage circuits would result in multiple codes like that. I would clear the codes and then try swapping the Engine Management Relaly with a known good part to see if the codes reoccur.

Gubernaculum · Post by **Gubernaculum** » 08 Dec 2012, 07:22

Replaced the brake pedal position sensor with a used junkyard one - no change.

I also pulled the accelerator pedal position sensor from a 2000 n/a V70, but I haven't put it in yet. Didn't see regent's post until after my junkyard run, so I didn't get a new relay.

I'm leaning toward just ordering a Xemodex next week since I feel like that's the most likely culprit (and I likely need to do it in the next 10k miles even if it's still passable right now) and I'm exhausted trying to troubleshoot.

Post by **precopster** » 08 Dec 2012, 14:26

Faultfinding with used electrical parts......wouldn't be my method unless it was off a running tested car. Relays are cheap but your code set would be different....still worth a try. Also the earth near oil pressre switch may have corrosion.

Gubernaculum · Post by **Gubernaculum** » 21 Dec 2012, 12:48

Just an update regarding the resolution of the problem above:
I ended up just replacing the ETM with a Xemodex unit, which cleared all of the above codes immediately and solved all the hesitation issues. It's expensive but I wish I had done that from the start rather than messing around with paying $50 to have my ETS light codes read and $15 pulling/installing junkyard parts. Hindsight 20/20 and all.

Also, although I pulled a junkyard throttle position sensor, I never installed it. I figured if I was getting the same hesitation when the cruise control was on (thus, no accelerator pedal position input), that probably wasn't the problem.

Post by **precopster** » 21 Dec 2012, 14:19

Thanks for updating the thread. After re-reading your post(s) I was beginning to be pretty sure you needed another ETM.

Gubernaculum · Post by **Gubernaculum** » 22 Dec 2012, 16:59

Yeah. I would have loved to do the SACER job, but now is just not a good time for me to be anywhere near the "cutting edge" of anything. Plus it really irks me that the supply chain for the part isn't figured out yet. I'm not paying $150 for a single part on ebay that costs $300 for 4 directly from SACER (they only sell in bulk) (my source for the $300 for 4 number is the distal terminus of my gastrointestinal tract, but that was the impression I got).

Post by **precopster** » 22 Dec 2012, 17:57

They cost a lot more than that, even from Sacer