Need some advice. My battery keeps losing charge and shorting out. Maybe a wiring or ECM short.

We had a windshield seal failure that dropped 2" of water into the floorboards of our Camry. The water appears to have flowed down the A pillar down the door jamb where the wiring harness and computer connections are. Here are two pics from the harness that appear to have corrosion or possibly shorted.

Does these connections look unusual?

Jason

 

You started having electrical problems after the water issue?

Does the car otherwise run OK?

What pillar, front passengers side?

How high did the water get. There are electrical harness plugs under the seat and lower to the floor.

There appears plenty of dialectic grease on the plugs shown. The grease keeps out moisture.

You can remove the individual wire plug pins from the back of the plug and check for corrosion. An internet search will show how.

Clean plug and pins with electrical contact cleaner. Remove corrosion with tooth brush, small wire brush, perhaps rubber pencil eraser. Reapply dialectic grease (this is an electrical grade silicone grease). Walmart or auto parts stores sell contact cleaner and the grease.

Any yellow wiring is airbag. Don't disconnect wiring then turn on ign key or the system will self check and turn off.

You can place a milliamp meter inline with a battery cable. Then ign ke off, start pulling fuses until the excess current stray stops.

 

Yes, this is the front passenger side pillar. Car was running fine until the battery started draining. It has now shorted two batteries, one was new. Should we try to change the battery again to do some of the tests you described?

There was about 2” water in the floor boards which means a lot of water came down the pillars and possibly down the inside of the firewall based on wet and mold patterns of the insulation. The car was never driven in flood water. All water leaked from the failed windshield seal.

I’ll try some of your suggestions. Thanks.

 

Its possible the battery drain can be from other issues such as the water. Does the car have a radio with remote amp (might be under the passenger seat) or automatic climate control? Is the brake or trunk light stuck on?

Just because a battery is drained to the point of being dead, doesn't mean it can't be charged up with a battery charger. However continued discharging of the battery will wreck it.

You can buy battery chargers at Harbor freight for under $30 and less with a 20% off coupon. Said battery charger could then be connected to the battery to charge it.

Plus when charging the battery it can also act as a replacement source of voltage for doing a current flow test outlined in a previous post..

The internet has links on how to test for parasitic drain on the battery.

If you are paying for replacement batteries a source of low cost batteries is an auto salvage yard.

Until you find the source of the drain, keep a battery cable discounted when parking the car overnight.

Another suggestion is to outline the path of the water entering the car and thee area where the water accumulated on the floor. These being the areas effected by the water. It might help to remove the passengers seat (4 bolts). Then with battery disconnected, disconnect, inspect, and clean any electrical harness plugs you find that might have been effected by water. Then once done, reapply the electrical grease and reconnect.

If the car has airbags make sure any airbag electrical cables are reconnected before turning on the ign key. The airbag wiring is typically yellow. The reason being the computer will run a self test and fail. Resetting the airbag requires it be done manually with a OBD reader.

Suppose its possible that the water may not have shorted something but is now preventing electrical contact. Make sure the alternator is charging the battery. The internet also has threads on checking the alternator voltage output to the battery. Basically this is just checking battery voltage at say 2000 RPM. It should be around 14-15 volts if alt is working.

If starting the car, make sure you have the battery cables connected to the battery. Meaning you don't still have the milliamp meter connected in series with a battery cable.

 

Thanks man. I already removed the carpet and all the related interior trim and padding to verify the source of the water leak. We replaced the windshield and seal so that seems to have fixed the water problem. Also noted that one of the firewall dash bolts right above the computer, harness, and stereo amp was pretty rusty where the water came down but the other bolts were okay, suggesting that was in fact the water path. Will recharge the battery and check the other things you suggested. Stay tuned...