'98 Explorer with the "4 Wheel High" and the "4 Wheel Low" lights flashing in sync

[drew.newman]

98 Explorer, Automatic, 4.0 L SOHC.

Tranny started acting up a few days ago, when I'd put it in gear it would act like it was being shifted into 4-wheel mode. Problem would clear itself when I'd put it back in park, pause, then back into gear.
I wanted to test it so i put it into 4-wheel mode, both high and low. it seemed like it didn't make the shift, then when i switched it back to normal it went into 4-wheel low and won't come out.
The tranny fluid is fine, no OBD light, the "4 Wheel High" and the "4 Wheel Low" lights are flashing in sync.
Thoughts? Thanks, Drew

 

[J_C]

I've never had this issue but have read where some people got it out of 4 low by putting it in neutral, then switching 4 hi or auto, then putting it in to reverse and backing up a little.

* I am poor at transmission diagnosis * but suspect either a bad transfer case shift motor or relay(s) powering it. If it's seized you might be able to gently tap on it with a hammer, or refurbish it, or I could be way off base...
http://www.explorerforum.com/forums/index.php?threads/how-to-rebuild-4x4-shift-motor.123542/

Since the lights are flashing you might be able to pull transmission trouble codes, if the scanner used is capable of it.

You could unbolt the shift motor to see if it's operating from the console switch, and if that's it, I'm surprised a new Doorman is only $70 on Amazon... don't know what it costs elsewhere like Rock Auto. This looks like the right one but double check part #'s before trusting that, and remember I may be wrong about everything I wrote:
https://www.amazon.com/Dorman-600-803-Transfer-Case-Motor/dp/B000C10D2M

 

[bryansr]

My 98 is doing the 4H/4L lights flashing sometimes. I could never figure out why, but it only takes removing the battery cable for a few minutes to reset it, then it shifts from 2H to 4L and back w/o problem.

 

[Mbrooks420]

The 4wd lights flashing indicates there is a fault in the 4wd system, just as the OD light flashing indicates a fault in the transmission. Did it make a clunking when shifting to low? In Nuetral or park with your foot on the brake? If it's stuck in low, you can pull the shift motor off and force it to shift with a wrench.

 

[96eb96]

Forscan is a free app that will allow you to do full testing on your 4x4 system. You use the same adapter as torque.You will at least get specific trouble codes.

Blinking 4x4 lights could mean the high-low shift was unsuccessful (it can't read the shift motor position, something is binding). When you cycle the ignition the shift motor is reset to its base position. You could take the shift motor apart and clean all the contacts.