Headlights going out

Hello thanks for the help. I have a 2001 tacoma 2.7 regular cab 4x4 manual transmission. My issue with the headlights started up in lake placid New York, it dropped below zero overnight. Somewhere around -8 plus wind chill. In the morning my tires were actually sagging it was so cold.
Since that day the headlights are much dimmer and dim while driving until they are nearly out. At which point (between 32-36 minutes) they turn off. I have to turn switch off than back on and the process repeats itself.
The battery was checked and was good.
The alternator was checked and was good
The rear trailer wiring I redid the ground on it to make sure
An aftermarket radio was put in but after this issue started (plug and play no wire changes to cause issues)
New silvania silver star headlights.
Also the auto shut off feature the headlights have where they shut off when you open the driver door stopped working at the same time(the chime still works when door is open though).

Any suggestions where to look?
Thanks for reading and the help.

 

Maybe your headlight relays are going bad or freezing?

 

I was thinking of just going and replacing them. Had a similar issue with battery dying on motorcycle when starter relay was going. Just don't want to throw money at random parts and hope. The relay has a good click when the switch is turned and does not get hot (which I would assume would happen if it had a short and built up resistivity causing the dimming of the lights) any way to check the relay?

 

Would the relay cause the auto off feature to no longer work?

 

They had a denso replacement at autozone for 19.99 so figured of give it a try with the relay. No change in condition tonight. Lights looked a little brighter but than again I also washed all the salt off the headlights. So still same problem no change in condition. Is there more electronics that are tied in. I still feel like it has something to do with lights not shutting off anymore.

 

Any ideas about the body ecu? Where it is located and of this could be the issue?

 

Sounds like the headlamp switch may be going bad. Have you tried manually jumping the headlamp relay and seeing if they dim down that way?

The headlamp switch in my 96 4runner is funky sometimes. I have to push in on the switch sometimes after turning on my headlamps to get them to come on. Once I do this it's fine until the next time I turn them on.

 

Shouldn't the headlamp switch just send low voltage to activate the relay? The switch functions fine ( everything turns on and off as it should and no play in lever or action). I can try that. The two toyota dealers their service departments say they haven't seen anything lik this yet

 

I think you're on the right track with the auto off feature. If the headlight circuit "thinks" the door is open you can still turn them on by cycling the switch. The battery saver will turn them back off after a given amount of time. My thought is the cold effected that circuit in some way that will probably be a bitch to find.

 

What other than the door switch controls that? I believe door switch is good lights inside still turn on and door chimes when open. I have headlight diagram but it doesn't show it tied in at all

 

And now my wipers turned on and won't turn off... Have to pull fuse

 

Now my wipers are stuck on and won't shut off only get faster. And the sprayer doesn't work. Think these are all connected?

 

My next best thought with your newest problem, would be to start checking grounds. The cold caused some metal contraction this could effect a ground connection somewhere. A lost ground will cause a computer to do all kinds of weird shit trying to diagnose the problem. Any codes?

 

Dim lights is usually an indication that the charging system is not healthy and not recharging the battery. First, clean and tighten all your battery and ground connections. If the dim headlights get brighter when you rev the engine, check the SoC of your battery. If the battery has a low State-of-Charge (SoC), externally recharge it. If the problem continues, fully recharge the battery and then load test both the battery and alternator. You could have an unhealthy battery, some open diodes in your alternator, undersized alternator, especially if you have added a large aftermarket load (lighting, audio system, winch, etc.) or driving short distances in bad weather not allowing the battery to fully recharge. The accuracy of Conductance battery testers can be greatly improved if the SoC is above 50% when the battery is tested.

 

The battery and alternator were checked by both autozone and someone I know to actually be competent. Both said they were functioning properly. The battery is less than 2 years old I do around 50-100 miles a work day highway driving. No aftermarket anything other than radio head unit. The battery connections are both clean and tight and change in revs does not change light output.

 

Is there a way to get a list of the ground locations? Just wondering?

 

Most factory electrical wiring diagrams will indicate common grounding points.
Typically, the primary ground connections are the battery negative post to the frame, engine block to the frame, and in some cases the transmission to the frame. With the increasing use of plastic, common ground connections for the lighting or dash are becoming more commonplace.

If you have a voltmeter, you can easily measure the difference between the terminal and what it is connected to for high resistance (voltage loss). A good low resistance connection should read zero voltage indicating no voltage loss. The high resistance connections are commonly caused by paint, corrosion, oxidation, rust, etc. Arguably, intermittent electrical opens are the most frustrating because they are difficult to find. Electrical wiring are one of the major causes (28%) of vehicle fires according the U.S. Fire Administration.

 

I checked the ground from battery negative to body and engine to body. Both were clean tight and corrosion free (removed and cleaned anyways). The wipers are working as they should again but the sprayer motor does not spray fluid. With truck off and headlights on the voltage drops very quickly (much faster than I would expect based on other things I've worked on (I own 2 cars and a boat from the 80s electric problems are normal) with truck running it sits between 14.04 and 14.12 without 12.75

 

I checked voltage at battery both running and not and with headlights on after 30 minutes it was same as before starting and than right after starting. The battery doesn't show signs of draw down with the dimming of the lights.

 

Brian, your observed voltages are exactly what I would expect. When you remove an absorption charging source, the "surface charge" on the plates will bleed off until it stabilizes at the battery's State-of-Charge (SoC). The amount of time, minutes to several hours, will vary depending on the health and type (plate chemistry) of the battery, load and temperature. A healthy wet Low Maintenance battery 100% SoC at 77 degrees F is 12.65 VDC after the surface charge is removed. A less common wet "Maintenance Free" or AGM will be approximately 12.8 VDC.

When testing your battery and charging system, did Auto Zone guy actually put a load of them? or just performed the normal conductance test on your battery and a voltage output test on your charging system? Have you checked the parasitic load? [I would expect it to be less than 150 ma] or the voltage drop across the lighting wiring and connectors?

In the Car and Deep Cycle Battery FAQ on www.batteryfaq.org, please see Sections 4 for more information on surface charges and load testing and Section 10 for testing and troubleshooting parasitic load problems.