Isuzu 2000 Trooper Workshop Manual page 940

A/C Clutch Control Circuit Diagnosis (Cont'd)
Step
32 1. A/C compressor relay removed.
2. Connect a fused jumper at the A/C compressor
relay socket between either BRN wire and the
BRN/YEL wire.
3. Engine idling.
4. A/C "ON."
5. Blower "ON."
Did the compressor magnetic clutch engage?
33 Repair the A/C compressor relay.
Is the action complete?
34 Check for an open circuit between the A/C compressor
relay and the A/C clutch.
Was an open circuit found?
35 Repair the open circuit between the compressor Clutch
and the A/C compressor relay.
Is the action complete?
36 Service the compressor clutch or replace the
compressor due to a faulty internal overheat switch.
Is the action complete?
37 1. Remove the A/C compressor relay.
2. Idle the engine.
Is the compressor clutch still engaged when A/C is not
selected?
38 Repair the short to voltage between the A/C clutch and
A/C compressor relay.
Is the action complete?
39 1. Reinstall the A/C compressor relay.
2. Remove the A/C thermostat relay.
3. Engine idling.
Is the compressor clutch still engaged when A/C is not
selected?
40 Use a DVM to check for a short to ground between the
A/C compressor relay and F4 of the PCM.
Was a short detected?
41 Repair the short to ground between the PCM and A/C
compressor relay.
Is the action complete?
42 Repair the short to ground between the A/C thermostat
relay and the electronic thermostat.
Is the action complete?
TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Action Value(s) Yes
Go to Step 33
—
— Verify repair
Go to Step 35
—
— Verify repair
— Verify repair
— Go to Step 38
— Verify repair
— Go to Step 40
Go to Step 41
—
— Verify repair
— Verify repair
6E–71
No
Go to Step 34
—
Go to Step 36
—
—
Go to Step 39
—
Go to Step 42
Go to Step 25
—
—