Soaked 2008 interior, no start and no check engine light?

[tenguns]

I have a 2008 Limited 4x4, V6. Got soaked inside. Standing water in the floorboards. Ran fine for a day or so. Then overnight the water intrusion stopped it from starting. No start and no check engine light.

Water soaked the wiring harness along the doors and may have got to connectors and or the ECU/ECM or ignition switch. Checked the fuses and relays in the engine compartment and all tested good with continuity. Checked the starter by jumpering the starter relay pins under hood. Turns over fine.

Pulled carpet up and dried everything. Took apart all connections and checked for corrosion, visible water damage. Nothing. Removed ECM to ck for visible damage. Nothing visible.

Just the ignition to the starter circuit doesn't seem to get power. Moved the shifter back and forth - park to neutral and nothing. Not even a click.

Interior fuse block - STA No.2 fuse lights up on start as it should. The only fuse in that under dash panel that doesn't ever have power ever is STA (7.5 amp.)

I pulled the starter relay again. Ground is there. Continuous power is there as it should be and when jumpering power to the starter solenoid the starter turns. But, upon turning the key I get only 5.9V from the neutral safety switch / ignition switch relay pin - and absolutely nothing happens. Think that pin is also supposed to be 12v not 5.9...

Is there an easy way to see if the ECU is getting power or is fried?
No check engine light or start signal.
Is changing the ignition switch a dealer only thing?
Every other feature in the 4R works, accessories, radio, everything -

I may have fried the ECU/ECM or there is something about the neutral safety circuit that is not working or its a bad ignition switch. Any ideas?

TIA

 

[Cezar]

Does the CEL come on when you turn the key to ACC?

 

[tenguns]

No CEL at all ever. Not in any key position.

 

[Cezar]

No CEL at all ever. Not in any key position.

Sounds like the ECU is fried.

 

[SocalSam]

I agree with Cezar. No dashboard CEL on key on, no ECM communication. Test ECM connector for power. It's also worth trying to clean connector and ECM pins. Try spare ECM. I think the replacement needs to be programmed to VIN.

 

[SocalSam]

IIRC, our cars have a chipped key which handshakes with an immobilizer module. The module sends command to ECM to allow start. Pray this is not the problem. Check ECM first.

 

[tenguns]

IIRC, our cars have a chipped key which handshakes with an immobilizer module. The module sends command to ECM to allow start. Pray this is not the problem. Check ECM first.

That must be a dealership thing then. $$$???

Just got new keys for it a year ago.

 

[tenguns]

That must be a dealership thing then. $$$???

Just got new keys for it a year ago.

Ordered a replacement ECU. Hope that works. Stealership doesn't seem like a valid option if something needs to be done with the keys. Tried the backup key - didn't work either but only have one keyfob.

 

[AuSeeker]

Ordered a replacement ECU. Hope that works. Stealership doesn't seem like a valid option if something needs to be done with the keys. Tried the backup key - didn't work either but only have one keyfob.

I don't think your issues would be with the key, I think the water shorted out the EXU so I think replacing it is the right move...BUT I do think that the new EXU will need to be programed to your vehicle's VIN number and the key's immobilizer system, so that might mean a Toyota dealer, unless you purchase a pre-flashed unit that was specifically coded to your VIN by the supplier.

 

[ArthurKotb]

You might try a mobile locksmith before the dealership. I've had good luck with one in my town that came to my house and reprogrammed a 2012 Corolla when both keys were lost. Then, when we found them, he reprogrammed them also. He used some kind of device that when he turned it on it cost me an extra few dollars but I got all 4 keys coded for the same car. Dealerships are expensive.

 

[hankd]

this is a known, repeatable issue on the 4th gen and there are lots of threads about it. if you get water near the driver side kick panel you'll short a wire in the nearby junction which fries the ecu even though the ecu is located near the glove box. this has happened to me. if you attach an obd2 scanner it won't light up and when you try and start the truck it's completely dead. although i could turn it on and get my accessories.

when you get the new ecu, don't install it until you have cleaned and dried the junction box in the kick panel. if it's still wet, it will fry the new ecu although it may take a day. ask me how i know this.

when you put the new ecu in, you will be able to connect an obd2 scanner and it will light up and identify the engine. you will also be able to crank the engine although it will not start. that is due to the immobilizer which is handled by the ecu. at that point you can tow the truck to any toyota dealer who can program the ecu to your existing key and fob. this cost me about 150CAN back in 2019. that's what worked for me anyway.

 

[ArthurKotb]

when you get the new ecu, don't install it until you have cleaned and dried the junction box in the kick panel. if it's still wet, it will fry the new ecu although it may take a day. ask me how i know this.

I don't suppose you have a picture of this box, or maybe a name? Can you give a better description?

You never know when / if something like this will happen and it's always good to know. Thanks for your post

 

[hankd]

I don't suppose you have a picture of this box, or maybe a name? Can you give a better description?

You never know when / if something like this will happen and it's always good to know. Thanks for your post

there is a big wiring junction visible if you remove the driver kick panel which is right at floor level. it's a blue box thing with tons of wires connected to it from various harnesses. so when you get the floor soaked that wiring junction gets soaked too. it took a day for mine to fry itself.

here is the video i watched when it happened to me to get a better understanding.

 

[ArthurKotb]

here is the video i watched when it happened to me to get a better understanding.

Thanks for posting the link to the video. It was very interesting but I don't plan on power washing my interior . Never can tell about flooding though. If that happens I would disconnect the battery and have it towed home to dry out.

The author complained about how low that connector was. Not knowing the history of wiring locations in previous years or problems like this one I don't know if there is a reason for doing this or for not making a water tight connection. I wonder if this issue is only for Gen 4.

Interesting point about him using a locksmith and then having an additional problem with the ECU and reprogramming the immobilizer. The guy I used explained everything he was doing for my keys and asked whenever he would have to do something different or charge extra. However, it's better to use the dealership for something like this. They know more about the intricacies of these units than locksmiths, I'm sure.

I hope I never have the problem

 

[SurferUK]

there is a big wiring junction visible if you remove the driver kick panel which is right at floor level. it's a blue box thing with tons of wires connected to it from various harnesses. so when you get the floor soaked that wiring junction gets soaked too. it took a day for mine to fry itself.

Never thought Toyota would have taken vehicle electrical advice from Volkswagen!

 

[ArthurKotb]

Never thought Toyota would have taken vehicle electrical advice from Volkswagen!

???
I missed something:noidea:

 

[hankd]

Thanks for posting the link to the video. It was very interesting but I don't plan on power washing my interior . Never can tell about flooding though. If that happens I would disconnect the battery and have it towed home to dry out.

The author complained about how low that connector was. Not knowing the history of wiring locations in previous years or problems like this one I don't know if there is a reason for doing this or for not making a water tight connection. I wonder if this issue is only for Gen 4.

Interesting point about him using a locksmith and then having an additional problem with the ECU and reprogramming the immobilizer. The guy I used explained everything he was doing for my keys and asked whenever he would have to do something different or charge extra. However, it's better to use the dealership for something like this. They know more about the intricacies of these units than locksmiths, I'm sure.

I hope I never have the problem

yeah super iffy on buddy power washing his interior like that. however he correctly points out the area that gets damaged. any time your floor gets soaked this can happen, it happened to me when i was offroading and got stuck in a water crossing. there are several threads on this forum with folks having the same issue when their floor got soaked. seems to be 4th gen only as far as i've seen.

 

[SurferUK]

???
I missed something:noidea:

They've been notorious for years (It was something I heard about in 2005 when I was looking at getting one) for putting the BCM in the footwell which then combined with their inability to design the scuttle panel in such a way it can't overflow or let water past the seal, then floods the footwell and fries the BCM.

 

[ArthurKotb]

Interesting. Since there doesn't seem to be a problem here after the Gen 4 it looks like Toyota solved that problem; maybe even before the end of that generation.

Years ago I had some Chrysler products and they all leaked at the left side wiper. With every rain I got a wet sock. I wonder if they ever fixed that.

 

[SurferUK]

Interesting. Since there doesn't seem to be a problem here after the Gen 4 it looks like Toyota solved that problem; maybe even before the end of that generation.

Years ago I had some Chrysler products and they all leaked at the left side wiper. With every rain I got a wet sock. I wonder if they ever fixed that.

Yes, I think submarine designers might have a case for calling water a cruel and unpredictable mistress - but not road-going vehicle designers. :madgrin: