89 Camry - defective lights indicator

Our 89 Camry has a dash light indicating one of the vehicle lights is malfunctioning. However every light bulb is working…so how do I trace the fault?

It is likely that there is no fault other than using light bulbs of different brands on the same circuit. Even though they can be labeled as the same type/number, bulbs of different brands will frequently draw slightly different amounts of electric current.

Since the “bulb burn-out indicator” works by comparing current draw on circuits that have pairs of bulbs, you need to go through all of the bulbs that are monitored by this device. This will include parking lights, tail lights, brake lights, and possibly things like license plate lights. On a 9 year old car, it is inevitable that a bulb or two has been replaced over the years.

Once you match the brand of bulb in each pair, the problem will go away. As wacky as this sounds, I discovered this as the solution to one of the problems with my Volvo many years ago.

This is the rear light out indicator. This light on the dash comes on if ANY of the rear lights are out. This includes the rear license plate lights.

If all the rear lights are working, then there may be a problem with the Rear Light Out module. This is located behind the left trunk panel. It’s a plastic box about the size of a pack cigerettes. Remove and unplug the module. Pry the cover of the module off and inspect the circuit board. If any burnt components are seen, the module requires replacement.

Tester

It’s actually 19 years old, so I agree most if not all of the bulbs have been replaced at some point. But I like you suggestion. I think I’ll have my kids make that their project this weekend!

Whoops! Yes, at 19 years of age, most of the bulbs have been replaced more than once, and you likely have a mix of many different brands of bulbs. However, it is only the bulbs on the same circuit that have to have the same brand of bulbs. For example, the license plate light bulbs can be of one brand, and the tail light bulbs can be of another brand, as long as you have matched brands on each circuit.

Do as Tester replied. Also make sure that the bulb(s) in the high mounted center brake light fixture are working as those also contribute to the total brake light current.

Yes there are two lamps in the high mounted center brake light. I know that both have to be working or the brake light malfunction warning will trip.

Well, all lights look like they are working. Time to inspect the circuit board.

I can see the yellow box but I can’t see how to remove the yellow box…how is it attached?

never mind…found it. The circuit board looks brand new…nothing fried.