Rear O2 sensor replacement questions

bluezero000 · Post by **bluezero000** » 01 Dec 2004, 19:52

The check-engine light on my 1996 Volvo 850 GLT is on and the error code shows that the rear sensor has no signal. From the tips on this board, a generic 4-wire sensor (#15717) from Bosch should work. When I asked a sales person at an auto shop, he told me the generic sensor doesn't have the right connector and I have to wire it to the connector of the old sensor. Is it true?

In OEM parts, there's distinction between upstream and downstream sensors, but there's only one generic type. What effect does it have if I use the generic one.

Finally, how do I reset check engine light and fuel adaptives myself? Volvospeed instructs to disconnect the battery ground for 10 minutes. Does it work on 1996 model? It seems 1996 model is different from previous models on resetting codes.

Thanks a lot.

Post by **matthew1** » 02 Dec 2004, 10:41

he told me the generic sensor doesn't have the right connector and I have to wire it to the connector of the old sensor. Is it true?

Yes, the harnesses do not match, or the generic does not come with one. Search this forum for more... someone detailed installation with that sensor and I think they spoke about the wiring.
https://www.matthewsvolvosite.com/forums/search.php

In OEM parts, there's distinction between upstream and downstream sensors, but there's only one generic type. What effect does it have if I use the generic one.

I don't know, sorry.

Finally, how do I reset check engine light and fuel adaptives myself? Volvospeed instructs to disconnect the battery ground for 10 minutes. Does it work on 1996 model? It seems 1996 model is different from previous models on resetting codes.

My 1997 light reset itself after one 'cylce' which in my case was about 2 days or ~20 miles. No battery terminal disconnecting.

bluezero000 · Post by **bluezero000** » 06 Dec 2004, 17:42

After I have replaced the rear O2 sensor, Check Engine light is still on after 50 miles. I'll try disconnecting the battery next.

Guest · Post by **Guest** » 06 Dec 2004, 21:02

Disconnecting the battery for 10 minutes to reset the fuel adaptives only works for 1999 and later models. I hope this helps

bluezero000 · Post by **bluezero000** » 07 Dec 2004, 19:32

Battery disconnection finally turned off the Check Engine light. Now I need to see whether it comes back on again -- hopefully not.