I posted this on renslist sometime back. I thought it might be useful here
P0341 & P01397on 1999 and older
Confused about the contradicting information posted on the web?
Here is what I found out.
The two camshaft sensors combine their signal output to pin 21 (red/grey) of the 5.2.2 motronics unit.
The output is active low e.g. it pulls the nominal 12V of the ECU to ground.
It fires once per camshaft revolution or every other engine revolution.
The two outputs are out of phase allowing the the ECU to figure out which signal is which bank.
Either cam sensor can cause this result as the ECU has no way of determining which is bad if the signal is garbage.
I messed with an intermittent that became solid and then was further complicated when one of the new sensors I bought (not bosch) was bad.
Here is my suggested trouble shooting and what I finally did.
Get to wire bundle in the rear trunk going to the ECU. Unwrap the cloth tape and find the signal wires (red/grey). There is one wire going into the ECU and it is soldered to two wires (one to each sensor) right there close to the ECU in the main wire harness.
Cut them free
Clear your alarms. (between steps constantly)
If you leave everything disconnected it will throw both alarms.
If you connect the bad sensor wire it will throw both alarms.
If you connect the good one it will throw the alarm for the bad one.
1397 is the left side sensor accessible through the inside access panel
0341 is the right side sensor which is under the Oil separator.
Make sure you label the wires to keep from getting confused
The left sensor is easy to get to and change.
The right side sensor is under the AOS which is not that hard to remove from the top with the right rear wheel off. One guy supposedly got the cam sensor off without pulling the AOS but he must of had small hands. and infinite patience. This is a good time to change the AOS anyway.
When you change the sensor measure the signals on the pins. The two outer pins should measure 5V between them and the center signal pin you cut free so you can ohm it back to the lead.
If you have an o'scope or graphing DVM you can clearly see the signals. Remember that the ECU is 12V with no input and that these pull it down to ground for the pulses.
ALSO this is only for the motronics 5.2.2 (99 and earlier) I think that is why there is so much confusion on the web.
I did not start this way and finally broke down and went into the wire harness and solved my problem in 1/2 hour,,, this was after a weekend of changing sensors. When I installed the new sensor that was bad the car starting running like crap. So although it will run with this error if the sensor is sending out garbage it can affect the running
Robert
Linear Mode
