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HVAC Fan - Inoperative in One or More of the Four Speeds

File In Section: 1 - HVAC

Bulletin No.: 46-11-03

Date: December, 1994

Subject:
HVAC Fan Inoperative in One or More of the Four Speeds (Replace Blower Relay and Connector)

Models:
1992-94 Chevrolet and GMC Truck M/L Vans with Air Conditioner (RPO C60)

Condition

Some owners of the above listed models may experience one or more of the four speeds of the fan to be inoperative.

Cause

High blower relay inoperative.

Correction

Replace connector and high blower relay with service kit using the following procedure:

1. Prep the vehicle. Be certain the negative ground cable is disconnected from the battery.





2. Remove the relay from the multi-use bracket. See Figure 1, View A.

3. Unwrap tape from the harness from relay back to major conduit.

4. Cut harness wires at base of original connector. This will provide maximum wire length for splices.

5. Using crimp connectors included in service kit (P/N 12166225 Blower Relay Service Kit), splice leads from numbered cavities on new connector to color coded leads from original harness as follows:

6. Splice lead from cavity 30 to purple lead.

7. Splice lead from cavity 86 to black lead approximately 1 inch further from connector than the first splice.

8. Splice lead from cavity 87 to red lead.

9. Splice lead from cavity 87A to dark blue lead.

10. Splice lead from cavity 85 to orange lead.

11. Fasten new relay (P/N 12077864 A/C Blower Relay) to newly spliced connector.

12. Reconnect negative cable to battery.

13. Test fan lever to verify there are four blower fan speeds. Re-check splices as needed.

14. Heat shrink each end of the five crimp connectors

Caution:
Care must be taken not to touch heat shrink wrap while still hot.

15. Harness all five spliced wires together with electrical tape from new connector back to major conduit.

16. Fasten new relay to multi-use bracket.

Parts Information





Parts are currently available from GMSPO.

Warranty Information





For vehicles repaired under warranty.