1999 explorer xlt 4.0 sohc | Ford Explorer Forums - Serious Explorations

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1999 explorer xlt 4.0 sohc


April 27, 2009
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City, State
port huron ni.
Year, Model & Trim Level
99 XLT
ok i have a a hard one the are some relays under the breather box can some one tell me what they do or a diagram to explain what each relay does. i do know that has to do with my transfer case i have the borg warner 4405-12 so if you can help please do i have been trying to get my front tires to spin i 4 wheel with the 4x4 lite on and in park i still can turn my front drive shaft i have been reading up on the transfer case an it seam to me that the cluthes are bad or the relay that engages it is bad so please help a fellow ford lover out i have know idea where to find the diagram i have a hanes an no diagram .:exp:

Sounds like your 4x4 motor is burned up. There is a how to on here somewhere.

None of the relays under the Air Filter (breather box) are related to the electronic transfer case. It is known as Aux Relay Box #1.


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The electronic 4wd system is controlled by the GEM (generic electronic module) and the TOD (torque on demand) relay. The GEM sends a PWM (pulse width modulated) signal to the TOD relay which then sends a higher current signal on a Brown wire to turn on the Transfer Case Clutch coil to engage the 4wd. If you search on Brown Wire Mod, you will find a lot more info. Both the GEM and TOD relay are located near the radio behind the dash.