Volvo "Bulb Failure Warning Light" malfunction

lights

#1

I own a 1991 Volvo 740 Turbo; a GREAT car!

A nagging proplem is that the Bulb Failure Warning Light comes on whenever I turn on the headlights (or parking lights). I have checked and rechecked all of the lights and I cannot find any inoperative bulbs. All looks right except that the Bulb Failure Warning Light remains on. Can anyone suggest what I may be missing? Thank you.


#2

The trouble may be due to a connection problem between one of the lights and the warning module. I would check the input voltages at the module to see if one of the legs isn’t working as it should be. The module itself may be at fault also. I don’t know where the module is for your car. If you want to work on this yourself I recommend you get a factory service manual for the wiring of the car. It is worth its weight in gold when working on these kind of problems and will save you time and money in repair bills. Other service manuals will get you by but usually don’t have the good details a factory manual shows you that really help in finding things like connection points. Ebay can be a good source for new and used service manuals at a good price.


#3

Make sure all the bulbs are the same wattage as the originals.


#4

Also, check your license light bulbs. As I recall, there are two of them. Also, you have to be very sure all of the tail light bulbs are working. Some cars have two on each side and it’s often hard to tell if they are both on. When in doubt, just replace all of them with bulbs meeting the OEM spec.


#5

I, too, thought I had a malfunctioning bulb warning light ('00 Camry). Took it to the dealer, where the Service Advisor (aka wallet cleaner) pointed out that the center brake light (inside the rear window) was out.

So, check again. Maybe some of the suggestions here will point out something you overlooked.


#6

as mentioned. change two of the bulbs. see if that helps. if it doesn’t help, replace two more. etc etc etc. this way you may luck out and find the bad bulb, and only be out the cost of two bulbs.

the high brake light suggestion is really appropriate too.


#7

Believe it or not, the solution could be very simple. I had a '74 Volvo, and it had the exact same situation that nearly drove me to distraction. Someone recommended that I check to be sure that both tail light bulbs were the same brand, that both parking light bulbs were the same brand, etc.

I replaced the bulbs that were of “odd” brands, and the problem went away, never to return. Be sure that you include the license plate light if it includes two bulbs, because the the sensor compares current draw between two bulbs on the same circuit. Believe it or not, the extremely minor differences in current draw from one brand of bulb to another can be enough to cause this problem.

Give this a try, and you just might luck out as I did. If only the major problems with that Volvo were as simple to resolve!


#8

The law of diminishing returns applies here. Why not just remove the bulb from the Bulb Failure Warning Light and visually check your lights as part of your weekly oil, coolant and other checks.

I use store windows, gas stations etc for light checks all the time, it’s an easy habit to get into. Sometimes the gadgetry on older cars just isn’t worth the trouble.

This of course is coming from a guy who hand built a new printed circuit for his 73 Chrysler’s Sentinel lighting system…


#9

Thank you to all (7) who replied. VDCdriver gave me the answer that corrected this problem. I changed out 4 tail light bulbs (all of which were working/lighted) with 4 new bulbs from one manufacturer and the dashboard warning light went off.


#10

TT

I’m really glad that my suggestion turned out to be the way to correct the problem. While I am always an advocate of referring to the Owner’s Manual, this is an example of some basic information that was not contained in the manual.

I’m glad that my experience with Volvos (note: overwhelmingly negative experience) was able to help you. I just hope that yours turns out to be more reliable than mine was, and I hope that solutions to your car-related problems continue to be this simple!