2008 Toyota Highlander intermittent start

[Rykertest]

Hello. 2008 highlander limited, V6, non hybrid, 190,000 miles. My wife said her car wouldn’t Start, that it was dead, lights and all. She heard a few clicks, the brake pedal was hard to press and then it went dark. I come home, check it and it starts up both with her key fob and mine, however, I had some odd symptoms. (FYI, when testing the fob I put one in a drawer at the other end of the house, then used the other and switched to use second fob)

The hvac screen didn’t have all the info it normally has for about 10 seconds and the clock was off by 8 hours so it obviously died at some point. Other than that, it started and ran normal. The battery shows 12.55 volts with the vehicle off and 14 volts when the vehicle is running. Based on those numbers, the fact it starts, I have no CEL, the fact that the battery is less than a year old and I see no corrosion on the terminals, I’m unsure of which way to go to repair this.

Any assistance is appreciated.

 

[Greasymechtech]

1 year old battery means nothing, especially if generic battery, or if not driving regularly. Might need to plug trickle/solar charger, if sitting for a few days without driving.

Sounds to me like either a dead battery, or its time to scrub/clean all drivetrain/chassis grounds. Might have some corrosion/resistance causing issues.

And, if the alternator is original, you should have it tested. I haven't seen too many higher mileage alternators doing too well at 190k and at its age.

Aftermarket alarm or remote starter could be an issue. Factory alarm could've fluked when she walked up to the vehicle. Too much can go wrong on an older vehicle.

How old are the remote batteries? I've changed all 8 car remote batteries here this past week, and every new years.

 

[D60]

Hello. 2008 highlander limited, V6, non hybrid, 190,000 miles. My wife said her car wouldn’t Start, that it was dead, lights and all. She heard a few clicks, the brake pedal was hard to press and then it went dark. I come home, check it and it starts up both with her key fob and mine, however, I had some odd symptoms. (FYI, when testing the fob I put one in a drawer at the other end of the house, then used the other and switched to use second fob)

The hvac screen didn’t have all the info it normally has for about 10 seconds and the clock was off by 8 hours so it obviously died at some point. Other than that, it started and ran normal. The battery shows 12.55 volts with the vehicle off and 14 volts when the vehicle is running. Based on those numbers, the fact it starts, I have no CEL, the fact that the battery is less than a year old and I see no corrosion on the terminals, I’m unsure of which way to go to repair this.

Any assistance is appreciated.

I've gotta wonder about battery cables and grounds further down stream

 

[Chris142]

Battery cables

 

[PimTac]

I've gotta wonder about battery cables and grounds further down stream

This. Check the battery and this as well.

 

[ripcord]

Others have given good advice. Also look for evidence of rodents or damaged wires in the harness.

https://www.amazon.com/QWORK-Terminal-Cleaning-Removing-Corrosion/dp/B09V7FMHKM/ref=sr_1_21?crid=3PA4ESRAKVTP3

 

[D60]

If it reoccurs try to have jumper cables handy or any heavier gauge wire. Just run a jumper from negative to any bare metal on the engine and see if anything changes.

Also I'd load test that battery as voltage at rest is only half the story

 

[mk378]

I'd still detach the battery terminals and make sure the contact surfaces on the terminal and post are perfectly clean. Then reattach, getting them fully down toward the battery. There should be some post showing above the top of the terminal. Also as others said inspect the main ground wire particularly where it attaches to the body and the engine.

 

[Rykertest]

1 year old battery means nothing, especially if generic battery, or if not driving regularly. Might need to plug trickle/solar charger, if sitting for a few days without driving.

Sounds to me like either a dead battery, or its time to scrub/clean all drivetrain/chassis grounds. Might have some corrosion/resistance causing issues.

And, if the alternator is original, you should have it tested. I haven't seen too many higher mileage alternators doing too well at 190k and at its age.

Aftermarket alarm or remote starter could be an issue. Factory alarm could've fluked when she walked up to the vehicle. Too much can go wrong on an older vehicle.

How old are the remote batteries? I've changed all 8 car remote batteries here this past week, and every new years.

It’s a Walmart battery so if that’s bad I’ll go visit them.

I looked over the cable connections, no corrosion at either end and snug connections. I don’t see any evidence of rodent damage but who knows. It’s always garaged and we don’t have any evidence of rodents.

No aftermarket alarms or starters.

The alternator could be suspect, I’ll swing by the auto parts store and see if they’ll test it.

The remote batteries did cross my mind. They’re about 1.5 years old.

Once I have the alternator checked I’ll report back,

Thank you for everyone’s help!

 

[Rykertest]

So the auto parts store said everything with their tester looks good. I just took it to a friend of mine who is a shade tree mechanic. He looked over everything and he checked all I did and couldn’t find anything. He used his volt meter to test the key fob battery and it was pretty low. He changed it and the car starts fine. He’ll keep it overnight and try starting it after it sits all night. The only thing that makes me think this isn’t the issue, or not a complete solution is the fact that the dash clock showed the battery had drained/died/disconnected at some point. At 9AM this morning it showed 1:30 or so. I don’t know how a key fob battery being low would cause that. So I made progress in eliminating an issue but unless someone can explain different, I think I still may have an issue to resolve.

 

[Rykertest]

Well, he says he’s pretty sure it’s the key fob. Can’t seem to get an answer as to how a low key fob battery could cause the clock to change but it starts and runs so I guess I’ll just see what happens.

 

[Greasymechtech]

Clock is a common failure. Limited means you have that little screen with a bunch of features(mpg/clock) and maybe the reverse camera???? It has a failure rate. I wouldn't tie it into your keyfob dead battery.

 

[Rykertest]

Clock is a common failure. Limited means you have that little screen with a bunch of features(mpg/clock) and maybe the reverse camera???? It has a failure rate. I wouldn't tie it into your keyfob dead battery.

Yes, that’s correct about the limited/little screen. I guess I’ll just wait and see what happens as we drive it. Thanks for your reply.

 

[michaelluscher]

Any chance there's a P0504 code?
For brake pedal switch correlation
I'd put fresh batteries in the keyfobs just to rule them out
You say the batteries new, still wouldn't hurt to have it tested

 

[Rykertest]

Any chance there's a P0504 code?
For brake pedal switch correlation
I'd put fresh batteries in the keyfobs just to rule them out
You say the batteries new, still wouldn't hurt to have it tested

No codes on my reader.