Etm/new TPS, not working what to check for?

Userrr420 · Post by **Userrr420** » 07 May 2018, 10:52

HELP! I REMOVED SENSOR and replaced WITHOUT CHECKING VOLTAGE. Poor instructions!Car still throwing code p0121( only code) where abouts is voltage supposed to be..wondering about adjusting magnet.. goes into limp mode immediately

Post by **firstv70volvo** » 07 May 2018, 16:35

I can provide you with voltages I measured on 3 different ETMs from the junkyard when I was replacing the throttle position sensor. After powering up the ETM with a 12V battery the throttle plate would go to a default slightly open position and the sensor voltage ranged between 1.38V to 1.43V in this position. When I held the throttle plate completely closed the voltage reading was between 0.58V to 0.64V. Full open the voltage was 4.47V to 4.7V. These are the voltage ranges for the 3 ETMs I looked at.

If you are able to adjust the sensor voltage by moving the magnet I would suggest adjusting the voltage when the throttle plate is held fully closed. From my experience the fully closed voltage level is most important to match with original voltage level. If original is unknown them 0.6V would be a good value to start with.
Note, I did have access to the voltage measure points on the outside of the side cover since I had ground off the plastic to be able to solder the external sensor wires to these contact points. Your measurement points will likely be different.

Post by **SuperHerman** » 07 May 2018, 19:10

Can any of this be done through VIDA? I know on my 2001 with the MM ETM that is how I handled it while fault tracing. I was able to cycle the unit and calibrate if I recall - ultimately I converted it to a pointless system as the MM ETMs had issues.

If you have access to VIDA, I would look there.

Post by **precopster** » 08 May 2018, 17:45

If you adjust magnet and voltages with plate in idle resting position with ignition on (or 12V applied from a power source) you will be fine.

Aim for 1.43 V as this is the exact centre of operation range.
ie. ETM will not start at below 1.24V and will not start at above 1.58V so 1.41-1.43 (being the average or centre) is the safest starting range.

Userrr420 · Post by **Userrr420** » 09 May 2018, 11:58

I will keep yall posted, Ill pull etm out of car and inspect this weekend. Thanks