backdoc

washed my car(97 A8Q) last thursday when it was warm here in upstate NY (55deg) and the check engine light came on when is was done washing it and started the car up. Since then it comes on occasionally. The codes are as follows:
17606- oxygen sensor heat circuit B1 S2: electrical malfunction.
17607- oxygen sensor heat circuit B2 S2: electrical malfunction.
16524- oxygen sensor B1 S2: no activity.
I have the Bently, but thought I would ask here first before going through all their procedures. It has been very cold here all week if that makes a difference. Thanks!
Doug
97 A8Q

PaulW

Did you wash the engine?

backdoc

NO.

Cjshutts

It is in the blue bank of fuses in the passenger footwell. I think it is number 4.

Since the heater current is too low for both left and right, it is probably not the sensors. The heater circuit current flows from the fuel pump relay through this fuse then through the heater in the o2 sensor then into the ECM (which measures the current).

If the fuse is good, pull up your floor mats and unplug the sensor. You can then check the heater voltage and the heater resistance.

PaulW

Just follow the Bently, all the initial troubleshooting is with vag-com.....after you have done that....if you have more questions, ask away....if you figure it out, post the solution!

backdoc

Thanks, Will do.