Bronco Not Starting After Car Wash?

[kennyle1990]

23 Bronco Raptor

so my car doesn’t like to start after car washes. I would start the vehicle and pull it out of garage so it’ll just be on for a minute or less. After the wash, it would start back up and I would reverse into the garage, once again, car would be on for less than a minute. But it’s guranteed not to start the next morning. Lights aren’t working, car won’t even turn on like the battery is completely drained. Only way to start the car is to use my portable car jumper and give it juice.

I have found that after the wash and reversing back into the garage, if I let the car idle for 5 minutes, then it’ll start up fine the next morning.

The car idling for 5 minutes, is this drying something??? Is there a sensor or something I should be drying off?? I’m just baffled at this. Thanks for any advice!

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[Area51BS]

Can only be 3 things in my opinion. Dead battery or bad connection related to battery. Except jump pack sort of rules connection out depending where you connect it.
Bad battery monitor or vehicles computer thinks the battery is bad. Have you broken out a DMM and done some basic voltage tests?

 

[tonytexchappy]

Maybe describe your wash procedure.
If the battery is weak, perhaps those two quick runs aren’t enough to recharge it after two starts.

 

[kennyle1990]

Can only be 3 things in my opinion. Dead battery or bad connection related to battery. Except jump pack sort of rules connection out depending where you connect it.
Bad battery monitor or vehicles computer thinks the battery is bad. Have you broken out a DMM and done some basic voltage tests?

If it’s a dead battery, then what I need to hire out is, what is it with a quick on and off of the car that’s causing it to drain the battery after a wash. And why is it that running the car in the garage for 5 minutes will prevent it from dying the next morning…

The jump pack was connected to pos and neg in the actually battery. I did check the battery and battery and terminal connection is all good.

 

[kennyle1990]

Maybe describe your wash procedure.
If the battery is weak, perhaps those two quick runs aren’t enough to recharge it after two starts.

I start the car and drive out past the garage and immediately turn off. Foam, rinse, foam, contact wash, blow dry, followed by a towel dry. Start the car, which starts up perfectly fine, immediately reverse and then turn off the car so throughout the entire process, car is not on for more than 2 minutes max. 7/7 times the car does not start the next morning but if I let the car idle for 5 minutes, 4/4 times the car starts the next morning

 

[tonytexchappy]

Battery’s biggest draw is on startup. If you’re doing that twice without giving it time for the alternator to charge, there might not be enough juice to start the next day. Next time, the second time you start it up, let it idle for the five minutes or more before turning it off and see if that helps.

 

[Brian_B]

Any stored DTSC codes? Or just no lights/no start/completely dead?

I'd try the reboot/trickle charge thing - it can't hurt and doesn't really cost anything. On the off chance it is a poor battery, that will fix it, but I think it may be more likely a computer somewhere maybe getting a wet connector from a bad seal and just doing something strange, and a reboot may clear that up somewhat too, or at least point in the right direction.

 

[RobWTX]

Probably not it, but try to disconnect the battery and clean the posts/terminals? Worth a shot maybe.

 

[indio22]

23 Bronco Raptor

so my car doesn’t like to start after car washes. I would start the vehicle and pull it out of garage so it’ll just be on for a minute or less. After the wash, it would start back up and I would reverse into the garage, once again, car would be on for less than a minute. But it’s guranteed not to start the next morning. Lights aren’t working, car won’t even turn on like the battery is completely drained. Only way to start the car is to use my portable car jumper and give it juice.

I have found that after the wash and reversing back into the garage, if I let the car idle for 5 minutes, then it’ll start up fine the next morning.

The car idling for 5 minutes, is this drying something??? Is there a sensor or something I should be drying off?? I’m just baffled at this. Thanks for any advice!

Wouldn't know ... haven't washed my Bronco since buying it in June 2023. Hope you find the cause.

 

[HeliPilot]

how about do the exact same procedure, pull out shut off/pull in shut off, only do not wash it. See if it behaves the same. If it does, then probably its the battery, if it does not then you probably have a grounding issue somewhere that water allows a draw on the battery.

 

[Lowcountry Bronco]

I start the car and drive out past the garage and immediately turn off. Foam, rinse, foam, contact wash, blow dry, followed by a towel dry. Start the car, which starts up perfectly fine, immediately reverse and then turn off the car so throughout the entire process, car is not on for more than 2 minutes max. 7/7 times the car does not start the next morning but if I let the car idle for 5 minutes, 4/4 times the car starts the next morning

Are you spraying water in the engine bay at all? If I wash out the engine bay I always leave it running and make sure all the connections are dry before turning it off. Also, do you have lights that you added or anything extra added to the electrics?

 

[Gtrekker]

Curious situation for sure...

If you are not washing your engine bay and you drive your Bronco regularly to where your battery is fully charged(?).

I'd would think you have a loose connection n water / moisture is getting to it n the Bronco thinks there's a fault with the battery.

Check all your cable connections are fully seated.

I fog n pressure wash my engine. Then let it run up to temp, hood open. Once the bulk of the water is dry, shut it down n let it steam off n cool. After I fog the entire engine bay with WD-40. No issues, ever.

Post if you find the cause. Imo, once started, it should at least be given time to warm up...

Please ur findings.

 

[Gregus73]

I have a Dewalt battery charger that I use about every 2 months. It keeps that battery charged and no issues.

it seems like there is a bit of drain on these batteries when the vehicle is parked. I was told if the key fob is near it exacerbates the battery drain.

I keep my electric mountain bike charged up every few months and after rides and no issues.

 

[Brian_B]

Usually, if its a drain from a factory component or system - the Bronco will go into Deep Sleep mode before it drains the battery down so far that it won’t start

But if you have some aftermarket stuff coming right off the battery, or maybe even via add-a-taps in certain spots, the Deep Sleep cant save you

Another thing to check are the tightness of the bolts on the fuse harness under the hood - if those are loose (and many have found them so) it can cause a lot of weird things

 

[Night Horse]

...After I fog the entire engine bay with WD-40.

So, you spray WD-40 on your entire engine, Sir? That stuff is flammable, so I'm just curious about this.

To add to the thread, I always wash the engine when I see dust. I do not pull the wand on the pressure washer, but let it spray lightly. I do this on every engine and never had an issue.

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