* Faulty Seat Belt Retractor: The most probable cause is a malfunctioning retractor in the non-working seat(s). These contain a spring mechanism and potentially a small motor (depending on the exact model's features) that might be jammed, broken, or experiencing electrical issues.
* Wiring Issues: Check the wiring harness related to the seat belts. A broken wire, loose connection, or corroded terminal somewhere along the path to the non-working retractor(s) could prevent them from functioning. This is more likely if *multiple* belts aren't working.
* Central Control Module (if equipped): Some vehicles, especially later models, have a central module controlling the seat belts. If your Camry has one, it might be faulty and not sending power/signals to specific retractors. 1989 models are less likely to have this, but it's worth considering if the problem affects multiple belts or other electrical functions.
* Fuses/Circuit Breakers: A blown fuse or tripped circuit breaker specifically for the seat belt system could be the culprit. Check your owner's manual to locate the relevant fuse or breaker.
* Body Control Module (BCM): The BCM handles several functions in a vehicle and a malfunction might affect the seat belts.
* Inertia Switch: Some vehicles have an inertia switch that cuts power to the seat belts in the event of a crash, to prevent accidental engagement. If this is improperly tripped it could cut the power to the retractors. However this is usually unlikely if the single belt was working properly and not in an accident.
Troubleshooting Steps:
1. Check Fuses/Circuit Breakers: This is the easiest and first step.
2. Inspect Wiring: Visually inspect the wiring harness leading to the non-working retractor(s). Look for cuts, breaks, or corrosion.
3. Test Retractor Function (with caution): Manually try to pull the non-working belt out and retract it. A completely jammed retractor will likely need replacement.
4. Consult a Repair Manual: A repair manual specific to your 1989 Toyota Camry will provide wiring diagrams and troubleshooting guides.
5. Professional Mechanic: If you're not comfortable working with car electrical systems, take your Camry to a qualified mechanic. They have the tools and experience to diagnose and repair the problem accurately.
Remember safety first! Don't attempt any repairs that are beyond your skill level. Driving with malfunctioning seat belts is dangerous.
