TEST
ACTION
APPLICABILITY
13
Turn the ignition off.
Disconnect the PCM harness connectors.
Turn the ignition on.
With the DRB, select Engine, Bosch Controller then Inputs/Outputs.
While reading the A/C Switch input, use a jumper wire to connect the A/C Switch
Signal circuit to ground at the PCM harness connector.
Does the DRB display A/C Switch ON?
All
Yes
→
Replace and program the PCM in accordance with the Service
Information.
Perform ROAD TEST VERIFICATION - VER-2.
No
→
Go To
14
14
Turn the ignition off.
Disconnect the PCM harness connectors.
Disconnect the ECM harness connectors.
Measure the resistance between ground and the A/C Switch Signal circuit.
Is the resistance below 100.0 ohms?
All
Yes
→
Repair the A/C Switch Signal circuit for a short to ground.
Perform ROAD TEST VERIFICATION - VER-2.
No
→
Go To
15
15
Turn the ignition off.
Disconnect the PCM harness connectors.
Disconnect the ECM harness connectors.
Measure the resistance of the A/C Switch Signal circuit.
Is the resistance below 10.0 ohms?
All
Yes
→
Replace and program the ECM in accordance with the Service
Information.
Perform ROAD TEST VERIFICATION - VER-2.
No
→
Repair the A/C Switch Signal circuit for an open.
Perform ROAD TEST VERIFICATION - VER-2.
16
Turn the ignition off.
Disconnect the A/C Heater Control harness connectors.
Disconnect the PCM harness connectors.
Turn the ignition on.
Measure the voltage of the A/C Select Switch Sense circuit.
Is the voltage below 1.0 volt?
All
Yes
→
Go To
17
No
→
Repair the A/C Select Switch Sense circuit for a short to voltage.
Perform ROAD TEST VERIFICATION - VER-2.
17
Turn the ignition off.
Disconnect the A/C Heater Control harness connectors.
Disconnect the PCM harness connectors.
Measure the resistance between ground and the A/C Select Switch Sense circuit.
Is the resistance below 100.0 ohms?
All
Yes
→
Repair the A/C Select Switch Sense circuit for a short to ground.
Perform ROAD TEST VERIFICATION - VER-2.
No
→
Go To
18
168
DRIVEABILITY - DIESEL
*CHECKING THE A/C SYSTEM —
Continued