Generator & Regulator: Other Volvo V90 I

BELT TENSION

Belt is self-adjusting.

S90 & V90

1. Connect voltmeter to battery. Run engine at 2000 RPM until voltage stops rising. Voltage should be 13.0-15.0 volts. If voltage is higher with integral regulator WITHOUT temperature sensor, replace regulator. If voltage is higher with integral regulator WITH temperature sensor, check sensor.
2. Temperature sensor is located under battery. Note battery temperature and charging voltage. Check Graph "A" to see if temperature and voltage are within center lines of graph. (Scheme 4) If so, charging voltage is okay.
3. If voltage and temperature is not within center lines of Graph "A", go to Graph "B" for internal temperature sensor check. (Scheme 4) Disconnect regulator temperature sensor. Locate temperature and voltage on Graph "B". If within center lines, replace internal temperature sensor. If not within center lines, replace voltage regulator.

Scheme 4