Electrical gremlins - no lights/no crank unless...

Good morning,

Odd issue with the electricals in my 09 TRDOR.

Occasionally, I'll go to start the truck and I get nothing - no dash lights, no crank, nothing. If I disconnect and immediately reconnect the battery, no problems at all for a couple days or weeks.

Battery tested good on a meter and a load tester. Alternator voltage meters good. IGN fuses and relays checked fine.

What might be the deal here? A relay sticking and going back to NO when the battery is pulled?

 

Try taking a battery brush to the terminals and posts. Sometimes the posts will become oxidized and look black.

When the problem happens, does anything work? Dome light, radio, headlights and such.

 

I hit everything with the battery brush when it first happened and it didn't seem to make a difference. When it does happen, the truck acts like there's no battery even installed, even though I get voltage with a meter across chassis ground and e.g. the far end of the starter run.

 

I would start with voltage drop tests on your battery cables and the starting circuit. Assuming they're the originals, there could well be hidden corrosion, wear, etc.

 

Worn out ignition switch.

Dirt and custodial load key rings are big contributors, but so are a bazillion key starts

 

Sounds like a cable issue? Enough voltage goes thru to register but craps out when load is applied?

 

Next time it happens, try turning on the dome light and see if the stop lights work.
Why? Because, this will let us know if we have power before the ignition switch.
There is a more thorough way of doing it, but this method is no tools required.

 

Hard to say; I'm suggesting that because: (1) It's easy; <5 minutes and requires only a DVOM; and (2) because the action effects the symptom. No start... remove cable... replace cable... start. It absolutely could be the ignition switch, or a host of other things, but I would start by verifying the cables.

 

check the bolt and fuse connection here.

 

I’ll go ahead and post this now, that way we don’t have to later

https://www.tacomaworld.com/threads...-box-battery-wire-replacement-upgrade.420450/

 

thanks, knew it was somewhere. My thoughts are if this bolt/nut setup is loose it can create a high resistance connection. You will get good voltage with no load on it.

 

I had an issue on my Honda where something similar would happen. The wireless key didn’t work, radio intermittent, no start, etc. I’d wait and while, it would “heal itself” for a bit. I find this



a few turns to tighten and problem solved.

 

That’s odd. Never see one of those back itself out?

 

I'm pretty familiar with the interior of the fusebox, I'll get into it when I have a chance next. Thanks for the input regarding the dome/brakes being before the ignition, too.

 

i bought the car brand new in 2014. Issue appeared around 2018 or so. I’m the only one that drives it. I made that “repair” in 2021 and all is well.

 

good luck and let us know what you find. The intermittent ones are the hardest ones to troubleshoot. Takes patience and methodical troubleshooting skills.

 

Things happen, that’s just one of the odd ones for sure

 

Check for rodent damage

 

a couple of teamsters will do quick work to those rats!

 

Something to mention. Close to the battery terminals, sometimes acid will wick up and under the insulation. Sometimes it’ll create a pregnant spot on the cable. Under the insulation at that pregnant spot the inner cable strands can become severely corroded and brittle. It’s pretty obvious so if you have that you would have noticed by now.

Another test you could do is a starter voltage drop test at the battery terminals. Then move the meter positive lead to the starter and test again. If there’s a significant difference you’ve got more resistance in the cable than you should. I had one, the difference was like .8v less at the starter. It ate something like 4 starters in 3 years.

My approach to a problem like this is to eliminate possible causes. Sometimes I’ll start with the easiest cheapest possibility. Sometimes I’ll start with the most probable possibility. Depends on my mood and level of patience at the moment.