02-12-2022, 11:33 AM
1996 2 door Geo Tracker 4wd
The 4WD light has been stuck on for some time, so I decided to dig into it today. Checked the transfer case 4wd switch first thing, it was fine. Traced and tested the wiring harnesses back to the firewall, found some questionable splices and wear and repaired those. Still stuck on, even with the switch disconnected.
Then I see in the service manual that the brake control module (EBCM aka ABS module) gets that wire too for some reason. So I try disconnecting the EBCM and boom the light starts working normally. So that makes me think the EBCM is forcing the light to stay on.
Trying to figure out why the EBCM would because forcing the 4wd light. Is it trying to complain about a fault? Is it malfunctioning and shorting the 4wd wire to ground? Any ideas?
The 4WD light has been stuck on for some time, so I decided to dig into it today. Checked the transfer case 4wd switch first thing, it was fine. Traced and tested the wiring harnesses back to the firewall, found some questionable splices and wear and repaired those. Still stuck on, even with the switch disconnected.
Then I see in the service manual that the brake control module (EBCM aka ABS module) gets that wire too for some reason. So I try disconnecting the EBCM and boom the light starts working normally. So that makes me think the EBCM is forcing the light to stay on.
Trying to figure out why the EBCM would because forcing the 4wd light. Is it trying to complain about a fault? Is it malfunctioning and shorting the 4wd wire to ground? Any ideas?