2002 QX4 ABS and 4WD Lights On

[Verycrisp]

I was wondering if these 2 lights are related. I recently got a solid abs light after starting the truck. Now after driving for about 30 minutes I get the 4wd light too. Could the 4wd light come from a bad abs sensor or do I have 2 separate problems?

[blkqx4]

How old is your alternator i had a similar issue it was alternator. Have it tested for proper charging.

[Towncivilian]

Try running the self-diagnosis procedure described on page TF-28 of the factory service manual.

[Verycrisp]

Thanks guys. blkqx4 my alternator checks out fine. Towncivilian I followed the steps and got 17 flashes from 4wd and what looks like a 25 and 21 codes from ABS. The 17 code explains a shorted ABS signal but the ABS codes state open circuits for both front sensors. Should I replace the front 2 sensors and see if that fixes my ABS, then move to 4wd, or will the ABS fix the 4wd?

[Towncivilian]

Have you ever flushed the brake fluid? Also, it may be worth disconnecting the front ABS sensor connectors and giving them a thorough cleaning with electrical contact cleaner. The ABS codes are most likely causing the 4WD light to illuminate as well.

[Verycrisp]

When I got the truck it sat a while so I changed the calipers, and wheel cylinders and flushed the system. I'm going to check the sensors, clean the connections and test again. Hopefully I don't have to replace them.