4wheelDrive Issues

[thaas1996]

So, I just recently bought my 99 Ford Explorer about a month ago. They guy I bought it from told me that the 4wd lights (high and low) had been blinking for a few months now and he didn't know what it was. I had been looking through this forum trying to find what it was, and I found many thing it could be some simple like the Shift Motor connections, to something big like a new transfer case. I was wondering what would be the most likely cause of the lights to blink. Could it also be something to do with the o2 sensors? I went to AutoZone and they told me I had 3 o2 sensors needing to be replaced, so I am about to replace them because with them being out, my X is getting HORRIBLE gas mileage, haha.... Anyways if anyone has any answers or comments about my question, PLEASE comment on it and let me know!

Thanks so much!
- Terry

 

[RomeovilleIL]

O2 sensors are completely unrelated the blinking 4wd lights. They would instead be indicated by the check engine light, which I assume is currently on. Honestly would be surprised at having 3 bad O2 sensors. What code numbers did they give you?

As for the blinking 4wd lights, they indicate an issue with the 4wd shift motor. Can be fuses, relays, or speed sensors. Could also be a bad shift motor.

Sometimes though its simply a case that the shift motor stopped between positions. Best advice is to disconnect the negative battery cable and press the brake pedal a couple times. Leave it disconnected for at least ten minutes, then reconnect the battery and start the truck. Put the transmission in neutral and with your foot on the brake switch the selector to 4wd low. May take a moment, but should hear the shift motor engage and flip to the transfer case. Once engaged, then flip the selector back to 4auto/2wd (depending on what your truck is labeled, its the position farthest to the left). Should hear and feel the transfer case disengage. This solves the majority of blinking 4wd issues.

Otherwise check these threads:
http://www.explorerforum.com/forums/showthread.php?t=135348&highlight=flashing+4wd+light
http://www.explorerforum.com/forums/showthread.php?t=165216&highlight=flashing+4wd+light

 

[thaas1996]

Okay man, thanks! I'll let you know if that fixes the problem!