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2005 Honda CRV headlights & instrument lights flicker

I’ve got a 2005 Honda CRV that I love everything about except one thing that really annoys and scares me.

The headlights and instrument lights “twinkle” or shimmer. Like they pulsate in intensity bright and dim 2- 4 times per second.

I’ve read threads in some forums and have heard of many other people experiencing the same problem but no solid solutions.

I’ve heard, low battery, bad battery connection, loose ground somewhere, loose alternator belt or faulty alternator, short in the wiring harness, or replace the dashboard computer.

I’ve checked many of these things but to no avail.

I’m worried that tracking this problem down could be severely costly and I’d like to have a better idea of what’s causing the problem or find a mechanic who’s experienced this before and knows the solution.

If anyone knows anything about this problem, the cause, or possible solutions, please let me know!!!

Sincerely,

Steve

What is the history of the battery? If it is still the original battery, I’d replace it and see if the flickering is resolved.

Your lights will dim and then get bright (flicker) every time a significant power draw occurs. You might have a faulty cooling fan that is cycling on and off rapidly, or the rear window defroster, or the AC compressor, stuff like that.

Looking at the schematic, it seems like those circuits have fuse 19 (100Amp) in common.
Pull the fuse and clean the contacts with some contact cleaner spray (radio shack) and/or insert/remove the fuse a bunch of times to seat the fuse well and get rid of the oxide on the contacts.

If that’s a common problem in that vintage CRV, they may not have designed it properly in that they’ve used wire that may be a bit too thin.

Which of the things you listed have you actually checked out? Have you had your battery & charging system load tested?

Ah good point. I now see the “I’ve checked many of these things but to no avail” part…

Using a volt/ohm meter set on the 20 VAC scale, connect the leads of the meter to the battery. Start the vehicle and observe if there’s any AC voltage at the battery. If there is, a rectifier in the alternator is starting to fail allowing AC voltage ripple to battery causing the lights to flicker.

Tester