GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Isuzu 🢒 2000 🢒 Isuzu MD Steel Tilt (F Model) 🢒 HVAC 🢒 HVAC Systems - Manual 🢒 Condenser Fan Inoperative

Step

Action

Value(s)

Yes

No

1
  1. Remove the A/C condenser fan relay.
  2. Use a test lamp from terminal 30 to ground.

Did the test lamp light?

Go to Step  2

Go to Step  16

2

Connect a test lamp from terminal 30 to terminal 87.

Did the test lamp light?

--

Go to Step  3

Go to Step  4

3
  1. Place ignition switch in RUN.
  2. Connect a test lamp from terminal 85 to ground.

Did the test lamp light?

--

Go to Step  10

Go to Step  6

4
  1. Install a fused jumper wire from terminal 30 to terminal 87.
  2. Disconnect A/C condensor fan motor connector.
  3. Connect a test lamp from cavity 6 to ground.

Did the test lamp light?

--

Go to Step  5

Go to Step  18

5

Connect a test lamp from cavity 6 to cavity 5.

Did the test lamp light?

--

Go to Step  27

Go to Step  22

6
  1. Remove the blower relay.
  2. Connect a test lamp from terminal 85 to ground.

Did the test lamp light?

--

Go to Step  7

Go to Step  14

7

Connect a test lamp from terminal 30 to ground.

Did the test lamp light?

--

Go to Step  8

Go to Step  15

8

Connect a test lamp from the blower relay terminal 86 to B+.

Did the test lamp light?

--

Go to Step  9

Go to Step  21

9

Connect a Digital Multimeter (DMM) from the blower relay terminal 87 to the A/C condenser fan relay terminal  85.

Does the DMM indicate continuity?

--

Go to Step  23

Go to Step  17

10
  1. Locate the vehicle in an area with an ambient air temperature greater than 10°C (50°F).
  2. Start the engine and maintain at 1000 rpms.
  3. Turn the A/C ON and position the temperature setting to COLD.
  4. Connect a test lamp from A/C condenser fan relay terminal 85 to terminal 86.

Did the test lamp light?

--

Go to Step  24

Go to Step  11

11
  1. Leave the test lamp connected in the A/C condensor fan relay terminals.
  2. Disconnect the A/C pressure cutoff switch connector.
  3. Connect a jumper wire from terminal 2 to terminal 1.

Did the test lamp light?

--

Go to Step  25

Go to Step  12

12

Connect a DMM from terminal 86 of the A/C condensor fan relay to terminal 2 of the A/C pressure cutoff switch connector.

Does the DMM indicate continuity?

--

Go to Step  13

Go to Step  19

13
  1. Disconnect the HVAC controller C2 connector.
  2. Connect a DMM from connector C2 terminal 3 to the A/C pressure cutoff switch connector terminal 1.

Does the DMM indicate continuity?

--

Go to Step  26

Go to Step  20

14

Locate and repair open CKT 371/198 (BRN). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

System OK

--

15

Locate and repair open CKT 190 (LT GRN). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

System OK

--

16

Locate and repair open CKT 201 (GRN/RED). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

System OK

--

17

Locate and repair open in CKT 191/204 (LT GRN). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

System OK

--

18

Locate and repair open in CKT 202/1727 (DK BLU/WHT). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

System OK

--

19

Locate and repair open CKT 205 (LT GRN/WHT) or CKT 1728 (DK GRN/WHT). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

System OK

--

20

Locate and repair open CKT 603 (DK GRN), CKT 206/216/177 (GRN). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

System OK

--

21

Locate and repair open CKT 199/21/550 (BLK). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

System OK

--

22

Locate and repair open CKT 150 (BLK) to G107. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

System OK

--

23

Replace the blower relay.

Is the repair complete?

--

System OK

--

24

Replace the A/C condensor fan relay.

Is the repair complete?

--

System OK

--

25

Replace the A/C pressure cutoff switch.

Is the repair complete?

--

System OK

--

26

Locate and repair open in CKT 174 (BLK). Refer to Wiring Repairs in Wiring Systems.

If no problem is found replace the HVAC controller. Refer to Control Assembly Replacement .

Is the repair complete?

--

System OK

--

27

Replace the A/C condensor fan motor. Refer to Condenser Fan Replacement .

Is the repair complete?

--

System OK

--