ABS and Brake light are on since my NV4500 swap. I also swapped the xfer case
It used to come on after a few miles of driving but now its on all the time.

I replaced the sensor in the differential but that didnt help anything.

Also I think my speedometer is off since the swap.

Any ideas?

 

threw a brake light switch in it...no luck

all fuses are good

could it be the speed sensor in the xfer case?

 

bump....anyone??

 

I'm no expert, but I'll give you a free bump. I don't know if your '97 has four wheel abs or not, but if all the abs speed sensors to not agree with each other, you will get the abs and brake light. I am hoping someone with a bit more knowledge will chime in to help you out further.
mishkaya

 

It's probably because the sensor in the transfer case and the one in the differential aren't agreeing on the truck's speed.
Tell you the truth I don't know how to fix it due to the swap.
May require a PCM flash by the dealer.

 

thats what I was thinking..I am going to try the 97 speed sensor out of my original transfer case

 

Try removing the abs sensor from the rear diff housing & cleaning it. I had the same issue & that fixed it for me.

 

Another related post said that the wire tends to fail right around where the harness connects to the frame. my lights are on now and next warm..ish day I'm going to crawl under and see if that's the case on mine.

 

The diff sensor is just for the speedo in the 4W-ABS versions, '94^ - the individual wheel sensors do the ABS -the trans\xfer case sensors are for the 47RE shifting, TCC lockup and o\d management in\out of 4WD Lo\Hi - check the wiring harness around the trans\xfer case - you may have pinched one or more wires during the swap-out, or possibly unplugged some connector(s) to the rear wheel sensors

The diff sensor is for the ABS in the RWAL versions, '97-back - the trans\xfer case sensors are for the speedo - still with checking wires\connectors around the swap area - the ground wire will affect both signals, so don't overlook the black wires

 

update....
I put the original speed sensor in the transfer case and that corrected the speedo, but the lights are still coming on. I am going to check the harness now.

 

I know on my '95s if the Brake/ABS lights come on the only way to get them off even after problems are corrected is with a scanner or to wait for 60 engine on/off cycles.
Disconnecting the batteries makes no difference but I understand it does on later years.
Mine both have 4w ABS if that makes a difference.

 

Yes, having the pre'98 ('94-'97) optional 4W ABS is the difference - the '94-'97 RWAL systems are more primitive - also, if you have the vacuum-boost system, low vacuum triggers the alarms via that module on the drivers-side fender - low vacuum is usually from a leaky hose, incl those going to the transfer case to operate the shifter.

 

this is a 97 rwal only

I checked the vacuum lines and they look ok....

I assume I need an ABS scanner to clear those codes?

 

I have had the lights on for a few months now. We tried to get to the ABS module for the code using a Dodge DTC and could not produce the code for repair. I was wanting to make sure it wasn't another issue first but the darn DTC won't even show codes when the lights are on! I haven't replaced the sensor yet but don't know what else it can be at this point. My lights come on after about 10 -15 seconds of run time, not right off the bat.

 

I think I am going to have to try the reflash of the ecm to see what it does....I am lost for ideas. I have looked and swapped everything