4WD High and Low lights flashing

[d524]

The lights are flashing occasionally and i'm no longer able to engage the 4WD into High or low. Would this typically be a speed sensor or the transfer motor? any suggestions or links to forum posts is appreciated.

Derrick

 

[Steeda90GT]

Try removing the negative terminal from your battery.

 

[gijoecam]

Try removing the negative terminal from your battery.

Won't fix the underlying problem. {rolling eyes} amazing... the 'bill gates' method of auto repair.

The lights mean the system has detected a fault and stored a code pin-pointing the issue. The bad news is that retreiving that code is less than convenient. Standard readers can't retreive the GEM DTCs.

Possible causes? Check for obvious signs of damage, specifically to the rear axle speed sensor and its associated wiring. Most people start by changing that sensor, and that tends to fix this problem about 75% of the time, but there are no guarantees. Without the code, it's a guessing game at best. The sensor is only about $15-$20, so it's usually worth a shot.

Good luck!

 

[Steeda90GT]

Please keep the condescending remarks to yourself. We're supposed to be a friendly-based community here.

While the rear speed sensor usually does go out on these trucks, they (most of the time) trigger the ABS light on the dash. How do you even know what the underlying problem is without properly scanning? Tons of times the computer reads out false errors. Even that PC/laptop that you're typing on could read out false errors with an application/security error (which 9/10 rebooting helps) Bring your vehicle to a mechanic with a trouble, and guess what the first thing they do is?

When this happened to me 3 years ago, I did the reset by unplugging the negative terminal. Guess what? 3 yrs/40k miles later my 4x4 still works fine and I haven't had a single warning light. Same with my brother-in-law. Over one year, running strong.

To the OP, give it a shot. It doesn't cost anything...worst case scenario the light comes back and you're in the same spot you were before.

 

[gijoecam]

Please keep the condescending remarks to yourself. We're supposed to be a friendly-based community here.

While the rear speed sensor usually does go out on these trucks, they (most of the time) trigger the ABS light on the dash. How do you even know what the underlying problem is without properly scanning? Tons of times the computer reads out false errors. Even that PC/laptop that you're typing on could read out false errors with an application/security error (which 9/10 rebooting helps) Bring your vehicle to a mechanic with a trouble, and guess what the first thing they do is?

When this happened to me 3 years ago, I did the reset by unplugging the negative terminal. Guess what? 3 yrs/40k miles later my 4x4 still works fine and I haven't had a single warning light. Same with my brother-in-law. Over one year, running strong.

To the OP, give it a shot. It doesn't cost anything...worst case scenario the light comes back and you're in the same spot you were before.

It was meant to be light-hearted, not condescending... My apologies if my remark was misinterpreted.

(edit: if I was trying to be condescending, I would have told him to search. )

Yes, you can try pulling the cable... But aren't you the least-bit curious what the code would be?

If you take it to a shop, the FIRST thing they're gonna do is pull the code. Then they'll clear it and see if it comes back. They're not going to just blindly reset the system. You'd be amazed what you can learn with the code in hand. if the light comes back on, how do you know if you're facing the same problem that caused it to come on in the first place, or some other issue? Unless you know that original code first, it's no less of a guessing game than swapping the rear axle speed sensor. (admittedly, it fixes the issue occasionally... In my experience here, maybe 10-15% of the time)