Blower Motor Inoperative at Any Speed - Auxiliary Air Conditioning (A/C). GMC Truck Savana 2000

For 1990-2009 cars only

Makes 🢒 GMC_Truck 🢒 2000 🢒 Savana 🢒 HVAC 🢒 HVAC Systems - Manual 🢒 Blower Motor Inoperative at Any Speed - Auxiliary Air Conditioning (A/C)

Blower Motor Inoperative at Any Speed - Auxiliary Air Conditioning (A/C) Cargo Van

Step

Action

Value(s)

Yes

DEFINITION:

•	The rear auxiliary blower motor will not operate.

•	Vehicle is a cargo van equipped with rear A/C (C69).

Did you review the HVAC blower operation and perform the necessary inspections?

Go to Step 2

Go to Symptoms in HVAC Systems-Manual

Place the ignition switch in the RUN position.
Place the auxiliary blower motor switch in the LOW position.

Does the blower motor operate?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

Disconnect the auxiliary blower motor low speed relay.
Connect a J 35616-200 unpowered test lamp between auxiliary blower motor low speed relay connector cavity C1 for CKT 1542 (RED) and ground. Refer to Circuit Testing in Wiring Systems.

Does the test lamp illuminate?

Go to Step 4

Go to Step 9

Connect a J 35616-200 unpowered test lamp between auxiliary blower motor low speed relay connector cavity C2 for CKT 341 (BRN) and ground.

Refer to Circuit Testing in Wiring Systems.

Does the test lamp illuminate?

Go to Step 5

Go to Step 10

Disconnect the front auxiliary HVAC control module.
Connect a J 39200 digital multimeter (DMM) between front auxiliary HVAC control module connector cavity B for CKT 150 (BLK) and ground. Refer to Circuit Testing in Wiring Systems.

Is continuity present?

Go to Step 6

Go to Step 11

Connect a J 39200 DMM between the front auxiliary HVAC control module pin C and pin B. Refer to Circuit Testing in Wiring Systems.
Place the front auxiliary HVAC control module blower switch in the LO position.

Is continuity present?

Go to Step 7

Go to Step 14

Disconnect the auxiliary blower motor.
Connect a J 39200 DMM between auxiliary blower motor connector cavity A for CKT 150 (BLK) and ground. Refer to Circuit Testing in Wiring Systems.

Is continuity present?

Go to Step 8

Go to Step 12

Disconnect the auxiliary blower motor resistor.
Connect a J 39200 DMM between auxiliary blower motor resistor connector cavity D and auxiliary blower motor connector cavity B for CKT 1172 (YEL). Refer to Circuit Testing in Wiring Systems.

Is continuity present?

Go to Step 15

Go to Step 13

Repair the open in CKT 1542 (RED) between the underhood fuse-relay center and splice S412.

Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 16

Repair the open in CKT 341 (BRN) between the instrument panel fuse block and splice S405.

Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 16

Repair the open in CKT 150 (BLK) between the front auxiliary HVAC control module and ground G400.

Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 16

Repair the open in CKT 150 (BLK) between the auxiliary blower motor and ground G400.

Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 16

Repair the open in CKT 1172 (YEL) between splice S413 and the auxiliary blower motor.

Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 16

Replace the front auxiliary HVAC control module.

Refer to Auxiliary Air Conditioning (A/C) Control Assembly Replacement - Front .

Did you complete the repair?

Go to Step 16

Replace the auxiliary blower motor.

Refer to Auxiliary Blower Motor Replacement .

Did you complete the repair?

Go to Step 16

Operate the auxiliary blower motor in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3

Blower Motor Inoperative at Any Speed - Auxiliary Air Conditioning (A/C) Passenger Van

Step

Action

Value(s)

Yes

DEFINITION:

•	The rear auxiliary blower motor will not operate.

•	Vehicle is a passenger van equipped with rear A/C (C69).

Did you review the HVAC blower motor operation and perform the necessary inspections?

Go to Step 2

Go to Symptoms

Place the ignition switch in the RUN position.
Place the auxiliary blower motor switch in the LOW position.

Does the blower motor operate?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

Disconnect the auxiliary blower motor low speed relay.
Connect a J 35616-200 unpowered test lamp between auxiliary blower motor low speed relay connector cavity C1 for CKT 1542 (RED) and ground. Refer to Circuit Testing in Wiring Systems.

Does the test lamp light?

Go to Step 4

Go to Step 14

Place the ignition switch in the RUN position.
Connect a J 35616-200 unpowered test lamp between auxiliary blower motor low speed relay connector cavity C1 for CKT 341 (BRN), and ground. Refer to Circuit Testing in Wiring Systems.

Does the test lamp light?

Go to Step 5

Go to Step 15

Disconnect the front auxiliary HVAC control module.
Connect a J 35616-200 unpowered test lamp between the front auxiliary HVAC control module connector cavity B for CKT 150 (BLK) and ground. Refer to Circuit Testing in Wiring Systems.

Does the test lamp light?

Go to Step 6

Go to Step 16

Does the auxiliary blower motor operate when controlled by the rear auxiliary HVAC control module?

Go to Step 7

Go to Step 10

Place the front auxiliary HVAC control module in the LOW position.
Connect a J 39200 digital multimeter (DMM) between front auxiliary HVAC control module pin C and pin B. Refer to Circuit Testing in Wiring Systems.

Is continuity present?

Go to Step 8

Go to Step 17

Disconnect the auxiliary blower motor.
Connect a J 39200 DMM between auxiliary blower motor connector cavity A for CKT 150 (BLK) and ground. Refer to Circuit Testing in Wiring Systems.

Is continuity present?

Go to Step 9

Go to Step 18

Disconnect the auxiliary blower motor resistor.
Connect a J 39200 DMM between auxiliary blower motor resistor connector cavity D and auxiliary blower motor connector cavity B for CKT 1172 (YEL). Refer to Circuit Testing in Wiring Systems.

Is continuity present?

Go to Step 19

Go to Step 20

Place the front auxiliary HVAC control module in the REAR CNTL position.
Connect a J 39200 DMM between front HVAC control module pin B and pin F. Refer to Circuit Testing in Wiring Systems.

Is continuity present?

Go to Step 11

Go to Step 17

Disconnect the heater and A/C control logic module.
Connect a J 39200 DMM between front auxiliary HVAC control module connector cavity F and heater and A/C control logic module connector cavity M for CKT 203 (LT BLU). Refer to Circuit Testing in Wiring Systems.

Is continuity present?

Go to Step 12

Go to Step 21

Connect a J 39200 DMM between heater and A/C control logic module pin M and pin L.
Use diode test setting on the J 39200 DMM.
Observe reading of the J 39200 DMM.
Switch the position of the J 39200 DMM leads on the heater and A/C control logic module.
Observe reading of J 39200 DMM.

Did the diode test good?

Go to Step 13

Go to Step 22

Place the rear auxiliary HVAC control module in the LOW position.
Disconnect the rear auxiliary HVAC control module.
Connect a J 39200 DMM between rear auxiliary HVAC control module pin C and pin F.

Is continuity present?

Go to Step 23

Go to Step 24

Repair the open in CKT 1542 (RED) between the underhood fuse-relay center and splice S412.

Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to Step 25

Repair the open in CKT 341 (BRN) between the instrument panel fuse block and splice S405.

Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to Step 25

Repair the open in CKT 150 (BLK) between the front auxiliary HVAC control module connector and ground G400.