Question: I did some work myself on my 2004 Tahoe to get rid of a clunking noise in the steering column. It looked like an easy job, so I replaced the steering column intermediate shaft. When I was done, the "Service Air Bag" light came on. What could've caused that?
| 2004 Chevrolet Tahoe Front View
Answer: Do a careful visual inspection of both the steering column and driver's seat wiring. See if any connectors are loose, terminals backed out, or wires broken at the harness going up the column to the airbag. If the column looks good, view the same stuff under the driver seat. There are switches and sensors relevant to the airbag system in the seat (seatbelt buckle switch, seat position sensor, etc.). If everything looks good, get the correct scan tool or a technician, and check the supplemental inflatable restraint (SIR) system diagnostic trouble codes. The code should give you a direct indication of where a circuit has been broken. Here's a possibility: When you removed the steering column intermediate shaft, did you secure the steering wheel? If you removed the shaft and the steering wheel or steering gear moved, and you then reinstalled the shaft out of sync, you may have broken the airbag cable reel (clockspring). The cable reel allows the steering wheel to rotate left and right, while maintaining a wired connection to the airbag. But this reel of wire only goes so far, and must be centered with the steering gear. Otherwise, you'll run out of wire while turning the wheel in one direction, and the wire will snap. For your model Tahoe, there's a special steering column anti-rotation pin used to lock the column before removing the intermediate shaft, and prevent an over-turn of the cable reel. If the trouble code is showing a break in the driver's inflator circuit, replace the cable reel.
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