212 error on 1995 850 turbo

poor_volvo_owner · Post by **poor_volvo_owner** » 19 May 2011, 12:12

I'm getting a 212 error, it says "S2 solenoid short circuit to battery". How do I resolve this? What/Where is the "S2" solenoid?

I recently changed the egr/pipe (from junkyard), so the 241 may just be a bad sensor. I still have the old one, to swap in.
There's also a 521 (upstream O2), and 153 (downstream O2). The downstream one was not changed. When I changed the upstream one, it had the wrong connector on it (came out of a '93 850), so I rewired it.

Comments? Suggestions?

Post by **Ozark Lee** » 19 May 2011, 13:19

What port(s) are you reading the codes from?

The S2 solenoid is in the transmission and if it was bad the transmission would behave quite badly, that code would be read from port A-1.

I show 2-1-2 as a front oxygen sensor signal error code for a '95 turbo if the code was read from port A-2.

Elaborate a tad more on what ports you are reading the codes from and we can work from there.

...Lee

poor_volvo_owner · Post by **poor_volvo_owner** » 19 May 2011, 19:35

Ozark Lee,

I am indeed using port A2. So, if 212 is a bad O2 Sensor, It seems to be in line with the other codes.
Now, I'm a bit perplexed, I went from 17 to 26 mpg with the new O2 sensor (junkyard). I realized it
could have gone bad (being used and all), but it seems like something else could be causing it.

Post by **jblackburn** » 19 May 2011, 19:40

Vacuum/other air leaks are the cause of like 95% of O2 sensor codes.

Check your vacuum lines! A can of carburetor cleaner sprayed around suspect lines will tell you if one's bad if you hear the engine speed up while idling.

Post by **Ozark Lee** » 20 May 2011, 00:28

+1 on what Justin said,

The usual culprit is the elbow off of the PCV that goes into the end of the intake manifold - strategically placed behind the alternator so that you can't get your hand in there to stick it back on.

There are times where it is very handy to have a diminutive daughter that is a good mechanic in her own right to put the vacuum line back on and save me the grief of pulling the intake manifold to get the job done.

...Lee

senna · Post by **senna** » 23 May 2011, 03:13

I had that problem in my 94 850T5 and it was a tube

Post by **pkc303** » 23 May 2011, 05:19

Pay particular attention to the elbows of the tubes. They have a way of going bad where you cannot really see them. Feel all the tubes and look for crumbly ones. Replace them.