4WD-Low Diagnostic Check ("K" Series With Manually Or Electronically Shifted Transfer Case In High Position)

1) Disconnect transfer case switch connector at transfer case. Turn ignition switch to ON position. Using a scan tool, monitor 4WD-low position. If scan tool indicates YES for 4WD-low position, go to next step. If scan tool indicates NO for 4WD-low position, check for internal short to ground in transfer case switch. Replace switch as necessary.

2) A short to ground in Dark Blue wire (Gray/Black wire on vehicles with VCM) between transfer case switch connector and PCM terminal F8 (terminal No. 23 on vehicles with VCM), or a faulty PCM/VCM is indicated.

3) Disconnect connector located behind distributor at center of torque converter housing. If scan tool indicates YES for 4WD-low position, go to next step. If scan tool indicates NO for 4WD-low position, check for short to ground in Dark Blue wire (Gray/Black wire on vehicles with VCM) between transfer case switch and connector located behind distributor. Repair wire as necessary.

4) Turn ignition off. Disconnect PCM Blue connector (Black connector on vehicles with VCM). Using an ohmmeter, measure resistance between ground and PCM Blue connector terminal F8 (terminal No. 23 on vehicles with VCM). If resistance is less than 100 ohms, repair short to ground in Dark Blue wire (Gray/Black wire on vehicles with VCM).