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J

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Discussion Starter #1
I've been looking at the 2004 electrical wiring diagram trying to figure out how the fog lights work/don't work.

It would appear that the wiring would permit the fogs to be on when the combo switch is either in park OR headlight mode. In the USA, they only work in the headlight mode.

My best guess is the ECU is programmed to only "complete" the circuit as long as the headlights are on AND in the "dim" mode.

Has anyone (here or abroad) played with this to change the way the fogs work? I'm specifically looking to turn the fogs on with only the parking lamps lit.

For those of you in the US with the wiring diagram: If I remove the 2 wire from the 3z connector of the passenger side ECU and then ground that wire, will this bypass the ECU interference (it theoretically should) and allow the circuit to be completed when I turn the fog light switch on with the combo switch in parking light mode?

(Sorry, but ya really got to have a wiring diagram or this is nothing but soup!).

jerij
 
N

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Discussion Starter #4
I noticed that the Factory Electrical Wiring Diagram Manual states that the fog lights should come on if the tail or headlights are on and the foglight switch is on.
p. 77, "Service Hints, Front Fog Relay:
5-3: Closed with the light control SW at TAIL or HEAD position and the fog light SW at ON position."
NOT! After actual verification, foglights can only come on if low headlights are on and the foglight switch is on.
In this modification, could you use a vampire tap to ground instead of cutting the wire? This way, to restore the OEM configuration, all you would have to do is remove the tap.
 
J

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Discussion Starter #5
It might.

When you look at the diagram of the headlight wiring and the foglight wiring, the ONLY thing/connection is the ECU/computer. My guess is the computer know when the headligts are in the "correct" setting, and therefore turn on the fog lamps. Best guess scenario is that you would have to remove the foglight/computer interface. As long as that ECU gets a signal it will keep the fogs off until you have the headlights in the right setting.

I'll just cut mine and ground it. You've got to ground it to complete the FL circuit. You've got to stop the ECU interface to let them come on.




jerij
 
E

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Discussion Starter #6
I was just looking for this mod.

When I saw this post I went and ground the cable and it work just great.

Thanks
 
J

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Discussion Starter #9
The wire does NOT have to be cut. I just grounded a connector wire and "plugged" the other end into the junction box connector. The computer can still send a signal to the wire to let the system know I've turned on the headligts in dim, but since the connector is already grounded, the fogs come on with the parking lights now.

I don't know if this will cause a problem with the computer/ECU, but it hasn't so far.


jerij
 
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Discussion Starter #10
Thanks jerij, that's just what I wanted to know, you can leave the OEM connection intact.
 
E

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Discussion Starter #11
to late I already cutted. :?

But is ok the mod is working! And I can fixed so no one knows it was ever done. :wink:
 
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Discussion Starter #14
Kelly Smith said:
This will most likely help with your project ---> CLICK HERE

Courtesy of - Antoine's RAV4 Page
Kelly,

My rav 2003 model has this socket connected to the tube where the horn wire are tuck in. Can this be used as 12v for relay of the horn or fadditional fog/driving light (mine has oem fog lamp (round)on the bumper).
 
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Discussion Starter #16
Kelly,

There is no socket under the metal frame infront of the alternator as posted.
What i found are sockets behind the headlights:

SOCKET WITH COVER



SOCKET WITHOUT COVER

 

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Bringing this thread back. Is there a way to get the foglights to be controlled only by the foglight switch independent of the headlights being on? I want to be able to use them as DRLs and turn them on and off whenever. Any ideas?
 

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cktannery said:
Where can one get hold of such electrical diagram short of purchasing the service manuals? Does anyone have a file of it?
I've got the 3 volumn set I'll sell you. Make me an offer. They are just collecting dust here.
Where in California are you?
I'm in South OC.
 
B

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Discussion Starter #20
Can anyone clarify which wires to ground?

Do I just goto the passenger side junction box and find a connector named 3ze and ground the wire?
 
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