Volvo 850 Supplement Manual page 13

ground wire. If only DTC 1-2-4 or 1-2-6 is present, go to next step.
2) Turn ignition off. Install test unit and adapter between
ECC control module and wiring harness. Turn ignition on. Connect
voltmeter to test unit pins No. 10 and 12 to check driver's side
temperature sensor and terminals No. 10 and 13 to check right side
temperature sensor.
3) Voltage should be about 2.6 volts at 68
voltage reading is 5 volts, check for open circuit in passenger's side
temperature sensor then go to next step. If voltage reading is 12
volts, repair short circuit between sensor harness terminal No. 5
(Green or Yellow wire) and ECC control module.
4) Turn ignition off. Disconnect Adapter (981 3194) from ECC
control module. Disconnect temperature sensor connector. Install
jumper wire between sensor harness terminals No. 3 (Brown wire) and
No. 5 (Green or Yellow wire).
5) Connect ohmmeter between test unit pins No. 10 and 12 for
driver's side temperature sensor or pins No. 10 and 13 for passenger's
side temperature sensor. If ohmmeter reads zero ohms, wire is okay.
Check for faulty sensor. If ohmmeter reads infinity, sensor is okay.
Check for open circuit.
6) To check sensor resistance, disconnect sensor harness
connector. Connect ohmmeter between sensor terminals No. 3 (Brown
wire) and No. 5 (Green or Yellow wire). Resistance should be 8000-12,
000 ohms. If resistance is not as specified, replace faulty sensor.
Clear and recheck for DTC.
DTC 1-3-1 & 1-3-3 DRIVER'S OR PASSENGER'S SIDE DUCT
TEMP. SENSOR CIRCUIT SHORTED TO GROUND
1) Ensure ignition is off. Connect test unit to ECC control
module. Check ground circuits and repair as necessary. See DTC 1-2-1,
OUTSIDE TEMP. SENSOR CIRCUIT SHORTED TO GROUND. If ground circuits are
okay, go to next step.
2) Ensure ignition is off. Disconnect A/C control unit, but
leave test unit connected to A/C control unit connector. Disconnect
driver's and passenger's side duct temperature sensor connectors. See
Fig. 8.
3) Check wiring resistance for driver's side duct temperature
sensor by measuring between test unit pins No. 56 and 47. Check wiring
resistance for passenger's side duct temperature sensor by measuring
between test unit pins No. 56 and 48. If ohmmeter indicates no
continuity, go to next step. If ohmmeter indicates continuity, check
wiring for short to ground.
4) Ensure ignition is off. Ensure driver's and passenger's
side duct temperature sensors are still disconnected. Measure
resistance directly between duct temperature sensor terminals. See
Fig. 9. Resistance should be about 8000-12,000 ohms. If resistance is
not 8000-12,000 ohms, replace duct temperature sensor(s).
£ £
F (20 C). If