Volvo Repair: volvo 850 1994, logical explanations, volvo 850 1994

Question
Hi Roger, I have four questions. We just bought a Volvo 850 station wagon 1994 model. We had to replace the gear for the odometer. Now, the rpm guage is not more working correctly. The pointer in the rpm guage is now way below zero, and when you crank the car, the pointer goes up to zero. It was working just fine before we replaced the gear from the odometer. Is there a way to reset the rpm guage? We also had to replace the light bulbs in the dashboard turn signal. So my husband cranked the car without having the passenger air bag pluged in, now the SRS warning light stays on all the time. Is there a way to clear the SRS code? Ok, my next question, the blower for the air condition and heating system is working fine on one, two, and three but not on the setting four(highest setting.) Can you please tell me how to fix it? My very last question(HOPEFULLY) is the back rest on the passenger seat is not working, you can't lay it down all the way, but the motor is running. What can I do? Thanks for your time!

                                       Delores

Answer
Delores, all fairly easy questions with logical explanations.  The Tachometer needle may have been bumped when the odometer was fixed.  Its all a matter of just realligning the needle.  The SRS can be reset manually.  Over by the Washer resevoir, there are 2 little computer sockets.  The one on the right is labeled B.  Put the connector thing that is on Socket A into B5.  Turn the key on, and hold the button in for 10 seconds and read the code. Example: 1-4-3.  Count the flashes.  After its read once, push the button again and count again.  Once it has read it twice, then hold the button for 10 seconds.   When  the light stays on Steady, then hold the button in for an additional 5-10 seconds.  Blower motor.  Check the fuse, there is one for position 4.  The seat back rest needs to have the seat cable repaired.  We do those at least once a week.  Hoped this helped.  Roger