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I have a 2002 Honda CRV ex with 100,000 miles. The instrument panel lights, map/dome lights, and the headlights flicker/surge. This is at idle and while driving. It doesn’t go away after the car is warm. Sometimes it is really bad, other times it is hardly noticeable. Took it to autozone for a charging/load test and everything checked out fine. Battery terminals are clean and secure. Any ideas? I’ve heard maybe voltage regulator. If so, how do I go about testing that?
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You came to the right place.
I used to work at autozone so please allow me to chime in on the issue at hand. Firstly, these people know nothing about cars. They can do basic battery, starter, and alternator testing and that’s it.
With that said, there is mostly likely a couple of possibilities here to consider, but first as with any electrical problem it’s important to cut through the b.s. and speculation and get right into the wiring diagram:
[i]
wiring diagram:[/i]One strategy when dealing with multiple affected devices on a circuit is to find commonalities that are shared among all devices. In this case, you have a common power feed; fused battery voltage which hits a splice point and feeds all your interior lighting. So.. at this point we have already identified a couple of points of interest: the battery and the splice point.
Just based on these items, I will recommend the following test that will address the two aforementioned points of interest:
Test #1
Perform a ‘voltage drop’ test on both battery terminals to check for unwanted resistance. The value you obtain should be less than .10 volts (or 100 mV) between the post and the terminal.Test #2
Since the splice point in the wiring diagram is unnamed or unlabeled, it will be difficult to find and test the splice point.. but all is not lost. Using the clues given and your ability to trace and follow wires, you should be able to find the white wire with blue tracer coming out of your fuse box. It will most likely feed through a ‘pass through’ in the bulkhead (firewall) and perhaps under the dash. In my opinion, this is most likely where the wire will splice into three white wires with blue tracer that will feed your interior lighting. This splice might appear as a type of connector or wiring harness. Nonetheless, it is a point of interest that must be tested because it can influence the entire circuit. Now, the test I recommend on this splice is a tried and true method called the “wiggle test.” (It is actually a valid test by GM and others) As the name implies, simply wiggle the splice pack and see if your lights flicker. If they flicker, you have most likely found the problem and can perform a wire repair of your chosing; whether it be solder & shrink wrap or compression splices.Side notes:
Since the affected devices do not share a common ground, I do not believe that the problem you are experiencing is necessarily a ground-side issue. I believe that this is most likely a power issue.
Just for fun, get a meter up in your lights and see what kind of voltage readings you are actually getting.
This may not be quite as easy, and it may mess up your meter if you are not careful, see if you can get an amperage reading for the entire circuit. (this could be made from anywhere in the circuit; the fuse box or a light for example.)
An uncommon phenomenon that no one ever tests for is a condition called “A/C Ripple.” Using your DVOM, check for A/C voltage from the alternator. The maximum allowed A/C current from the alternator should be less than .1 volts (or 100 mV.)
Here are some applicable videos that will help ye’ on your endeavors:
http://www.youtube.com/watch?v=zb7WHaL_dz8&playnext=1&list=PL0242A27608371154&feature=results_video
Great post above Wrench Turner. I would pay particular attention to the battery cables and connections as pointed out. One more thing you might want to check is the ELD or Electric Load Detector which I believe is located in the under hood fuse box. Sometimes they go bad and cause problems similar to what you describe.
Forget the ELD for now. I just remembered that all that stuff runs through the dimmer switch. Try ‘jiggling’ the switch to see if the problem happens. If it does then I’d recommend replacing the dimmer switch and rechecking for the problem. I’ve run into this issue in the past and the dimmer switch was the cause. It’s worth checking if nothing else. Also, if you have an aftermarket stereo this is also suspect. It might be better to say the wiring of it is suspect. If you don’t hook things up correctly it can effect the dimmer circuit for the vehicle.
Forgot to update this thread, sorry. Dimmer switch was fine, ended up replacing the ELD since it is only $23. Solved the problem 🙂 . I kept putting off this repair because I thought it was the alternator or something expensive. Thanks for the help!
Unfortunately I’m back. After replacing the ELD my car seemed fine for awhile. But things got a whole lot worse. About 4 hours into a 9 hour trip, the lights started to surge really badly. The surging stopped when both of my headlights blew out at the same time. Luckily I was 3 miles from a Honda dealership. They replaced the bulbs and sent me on my way as I needed to reach my destination that night. They didn’t see anything apparently wrong with the car and told me that a common light switch recall on my car had been taken care of already. On my way home the surging started again, only this time it caused my SRS light to illuminate (never have seen this before). Once I slowed down the SRS light went out and the surging became less.
I am currently selling this car and would like to try and figure out what is wrong before I sell it. I’m totally stuck. Battery has been checked, new ELD, alternator checked, dimmer switch checked…
Any ideas? Or should I give in and take it to a professional?
If the headlights blew out, there is just one possibility– the alternator sometimes get stuck on full on. There is no other way to blow out the headlights.
Your typical simple test at Autozone will not detect this.
[quote=”grg8888″ post=81985]If the headlights blew out, there is just one possibility– the alternator sometimes get stuck on full on. There is no other way to blow out the headlights.
Your typical simple test at Autozone will not detect this.[/quote]
That is what I am wondering, if his alt is full fielding while driving and sending too much voltage into the system.
Like above, if the headlights were effected like that my starting point would be the alternator. There are several things to test with an alternator. The easiest is to test the battery voltage while its running at idle, then turn on some of the accessories and fan and test it.
You can test an alternators amperage output also but not all multi meters will do it.
Another good one is to turn on a bunch of the accessories and then test voltage drop between the alternator case and battery negative. Eric has some great videos on the charging system.
Another thing to consider in your diagnosis is the weather. Where I am is cold, rainy, some snow and dark early. This time of year there is far greater load on your electrical system. A cold engine is harder to crank, constant headlight use, window defroster, wipers, fan etc. If anything in the charging system is getting tired it will start to fall behind and fail as soon as it gets cold. Ask any mechanic where they get winter what the most common repair is from late fall until spring: Battery replacement, and Alternators.
Took it to dealer and battery failed this time. Said it is holding a charge fine but the cold cranking amps are low. Battery isn’t new so this doesn’t surprise me. It is really cold here but I haven’t had problems starting it, even below zero.
Could an old battery cause this many problems? Or is it still likely something else like the alternator?
If it could be the batter I can try replacing that before I sell it. Alternator I’m not replacing though.
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