QuestionModel 850 T5 wagon, april 1995 (166kW) European version
Description of mulfunction:
Interior air on left side (next to steering wheel) was dead first, later complete system died, all lights work, all switches rotate, but air-motor does not come on. Recirculation engine seems to work, but cannot be sure. All fuses (nr 5 and 31 especially) are OK. Have checked airtubes and all seems to be in mint condition. Have taken motor (6820812) and resistor (9134932)(combined with relay ?) out for testing. Found that resistor is electronic, probably thyristor chopper type, hence cannot be measured easily.
General questions:
Q1: what could be the cause of the malfunction, both primary (partly disfunctional on left side no airflow) and later (complete malfunction)(workshop asked and said: resistor or motor: I add in-dash air-setting-electronics as well, but not sure)
Q2: What is the quickest and safest way to test for the malfunctioning part ? (if any)
Q3: are there causes outside the air-system itself possible ?
Specific querstions:
Q5: how to safely test the resistor
Q6: how to safely test the motor (e.g. what should be the coil resistance, if any, etc.)
The service manual I obtained all exclude specifics for the T5 model, as I found out and the colorcodes of the electronice wiring diagrams do not match the cars, I teherfore do not trust the manual at all, hence these questions as a precautionary measure.
I am a qualified electronic engineer, and as a hobby try to fix my own cars (4)
Any answer would be welcome.
Answernot sure whay one side then the whole thing.there a re dampener motors for each side that control temperature one on the left may have been bad and now the motor is bad.
quickest way if the car is electronic climate control is with the volvo system tester that will give codes for faults.
doubt there are causes outside the system.
to test motor supply it with a power and ground and see if it works.this will however not tell you the amps it is drawing.
not sure on the resistance of the motor. if you give it power and ground and it will not run it is bad.
try checking for codes first below is how to do so.email the codes I will tell what they are.
as for the motor if I were working on it I would replace them both as they both go bad.
behind the passengers side head light are 2 small black boxes,1 marked A ,and 1 marked B.on box A there is a small wire insert the wire into the hole marked 1 on box B then turn the ignition key to position 2 but not started.then on the box narked A push the small button for 1 second then release it.the small red light will flash a code back as a 3 digit number.there is a short pause between flashes for a single digit and long pause between the different numbers.example:
a 121 would look like this flash.....flash..flash....flash
write down each code,then after the first code repeats its self then press the button for 5 seconds the light will light when pressing button then go out when released,then the light will light steady again when it does press button fo 5 seconds again,this should have cleared the codest..
