Parasitic Leak FIXED.... but a few questions

[poitee]

A few weeks ago my 4runner would not start... Tested the battery and the dealership said it was bad and replaced it under warranty...
A few days ago the symptoms returned and I was fearful it might be the alternator.. I had it tested and everything came up good..
I started checking for parasitic leaks and could not find anything obvious causing it.

This is when it gets fun..... After pulling a million fuses it felt like I unhooked the hot lead going to the main bus panel up front and the drain stopped.... Must be in that panel right? So then I unhook the starter, alternator, and AC motor.. the drain is still there... Mind you after pulling all the fuses one at a time in the panel I still could not get the amperage draw to drop below 2.5amps.. So... I revert back to my profession.. I stop by the fire station and leave the truck sit outside in 20degree weather for about 2 hours and come up with the thermal imaging camera... sure enough.. the only relay showing hot was the dome light relay... pulled it... no drain.. no dead battery this morning... All the dome lights are off.. all the doors were shut.. Im assuming either a bad relay or faulty door switch.. Any ideas?

Thanks

 

[jwyshrek]

If the dome light relay is stuck closed or if it is a bad switch...should you see one of the interior lights stay on...especially at night and after you lock it???

Make sure that all of your interior lights are off...check the over head console, center dome light and cargo light...I believe all have a switch to override the door switch.

Now, having said that...I believe the 4th gen has a 'smart' lighting system which will turn off the lights after a certain period of time to prevent battery drainage...unless the relay was stuck or it thinks a door is open.

I would use a multimeter and check the continuity between the contacts of the relay...it should be 'open'...if it is not (shorted), then it is a bad relay.

If the relay is good, then may be a bad door switch...you'll have trace the wiring and find out which one is stuck 'closed'.

 

[poitee]

If the dome light relay is stuck closed or if it is a bad switch...should you see one of the interior lights stay on...especially at night and after you lock it???

Make sure that all of your interior lights are off...check the over head console, center dome light and cargo light...I believe all have a switch to override the door switch.

Now, having said that...I believe the 4th gen has a 'smart' lighting system which will turn off the lights after a certain period of time to prevent battery drainage...unless the relay was stuck or it thinks a door is open.

I would use a multimeter and check the continuity between the contacts of the relay...it should be 'open'...if it is not (shorted), then it is a bad relay.

If the relay is good, then may be a bad door switch...you'll have trace the wiring and find out which one is stuck 'closed'.

It does have the smart lighting.. everything is off... I'll check the relay and see.. If not I suppose Ill start on the doors.. To elaborate furthur... with the doors all closed when I would reconnect the negative terminal I would here the relay click...

Thanks!

 

[jwyshrek]

if you hear the relay click (with all doors closed)...then most likely, the relay is probably good...it clicking when you plug it in means that the BCM (body control module) 'thinks' one of the doors is open or will be opened (like when you first unlock it, the dome lights come on).

To make double sure, I would still meter the relay contacts...

Oh, one thing...when you plugged in the relay with the doors closed...did you plug it in immediately after closing the doors or did you wait a few minutes? Reason I ask, the 4runner has what they use to call 'theater' lighting...the lights slowly fade out after the last door is closed instead of going off immediately...unless you press the key fob to lock it...

Actually, to clarify...when you plug in the relay and reconnect the negative cable...do the dome lights come on?

If they don't...something is a miss...then might need of the other members to chime in with a wiring diagram...

 

[Asmara]

Although I can't see it pulling 2.5 amps, did you replace your dome lighting with LEDs?

Normal incandescent bulbs have built in resistance that prevents electricity from flowing when off. There is usually still a small amount of current present in the circuit despite that the lights are off.

In my other car, I swapped in LEDs and if I am in a completely dark space, I can still see them glowing a tiny bit. It isn't using enough current that I'm having issues but it is using some.

 

[mooligan]

New to the forum and apologise for a 10 year thread resurrection, call me Lazarus but this is the only thread that google shows for the exact same problem I'm having. Just bought a very neglected 2007 4runner sport for dirt cheap and going to bring it back to life as an almost daily driver. The thread says parasitic leak FIXED but doesn't mention the fix and doesn't look like the original poster does much here with only 2 posts, anyone got a clue as to the FIX. The relay gets warm, wiggled all the door switches etc, would be handy to know what it was.

 

[riceandpho]

New to the forum and apologise for a 10 year thread resurrection, call me Lazarus but this is the only thread that google shows for the exact same problem I'm having. Just bought a very neglected 2007 4runner sport for dirt cheap and going to bring it back to life as an almost daily driver. The thread says parasitic leak FIXED but doesn't mention the fix and doesn't look like the original poster does much here with only 2 posts, anyone got a clue as to the FIX. The relay gets warm, wiggled all the door switches etc, would be handy to know what it was.

looks like the op said it was his dome relay, you can swap those out and see if it helps.

 

[mooligan]

Thanks for the reply, I managed to sort it out, the relay was getting warm when everything was off and doors locked but it was working and not the problem - it'd click when plugged back in after removing it. What I did was wiggle all the door switches and push them in and out a dozen times and slid the dome light slides back and forth quickly end to end and bingo no more warm relay or battery drain. Just find it weird that the dome lights went out but the relay got warm and batt drained, must have been a short to ground in one of the switches, the rear dome switch was in between door and off position so think that was the culprit; truck had sat for about a year before I rescued it.