Volvo: 1997 volvo 850 warning lights, wheel sensors, sensor light

Question
QUESTION: Hi,
The warning light for my ABS system and the Check Engine light have been coming on in my car on a regular basis. They seem to switch off. The error code for the Check Engine light is P0410 and I went to a mechanic who pulled out the relay for the secondary air injection system and it was filled with water.  I have been trying to find a replacement for the relay, but have only found air pump relays. Are they the same? Also, the ABS warning light goes on and off, I don't know what this could mean. Finally, my coworker tried disconnecting the battery for my car to see if any of the warning lights would clear. This caused the ambient temperature sensor light to turn on, and now it stays on all of the time even when the car is off. The temperature also doesn't show up any more.  I checked the manual and it said if I press the hour and minute buttons for the clock at the same time, I can restore the temperature, but this does not seem to work.  Could you please help me with any of these issues? Thank you very much!

Sincerely,

Terry

ANSWER: Terry,
For the relay give me the part number off the relay and I'll look to see what might work. What you found the "air pump relay" sounds like the right one. Why do you question it? It maybe a matter of calling the system Secondary Air System vs. Air pump.
On your year car the ABS has had many control unit issues. Most time I read the codes and find faults for rear wheel sensors. I replace the control unit and the faults go away. There are cracks that happen in the control unit PC board and that sets the rear sensor codes.
Dash temp as far as what I have seen when the battery is disconnected and reconnected the light lights and goes  off unless the sensor is disconnected.


---------- FOLLOW-UP ----------

QUESTION: hi,
Thank you. The relay says:
Fan -Relay 3523871
89 9900 000
>PA6-GF30<

Thank you.  
As for the dash temp and ambient sensor light, where is the sensor? How do I check if it is disconnected?

Thank you again for all of your help.

Answer
Terry,
The relay number you supplied is the relay for the SAS system. Temp sensor is in the spoiler behind the lower air dam. Maybe the wire has broken. If it is not disconnected you will need the help of a know good sensor to try. The Volvo book does not list a specific way to diagnosis it.