Where is the location of the 4WD control module on my 2008 Ford F-150
Without turning the knob to 4x4 high range the left front lockout wants to kick in. With a quick turning the knob toward 4x4 hign range and back to 2WD disengages the lockout. With the vacuum valve disconnected it still does it. An electrician says that it is the 4WD control module is bad because the vacuum valve is getting the signal to open at randam.
Check your owners manual as it shows the location of the various relays. Most likely it is under the hood.
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