1998 Navigator NO low range

[rockinrolla]

Hello everyone I'm a newbie. I have a 1998 navigator i just got recently and cannot get 4x4 low to work it has the selector dial options for 2wd,a4wd,4hi,4low. The A4wd and 4 high work fine can hear relays clicking and motor engaging 4 hi. I've tried stop depress brake and put in neutral and switching to 4 low nothing no clicking or motor sound I've checked all the wiring to the shift motor and check for corrosion nothing.The actuator is working all the fuses are good. I pulled the shift motor and manually put it in 4low with pliers and it works so it's not the transfer case.I watched the motor off the transfer case while someone else put it in low range and the motor did not spin any thoughts? thank you. Also the low range dash light has never come on even when i first start the truck

 

[bedrck46]

The Vehicle Does Not Shift Between 4WD HIGH and 4WD LOW Modes Properly

A4WD mode switch/circuit.
VSS.
BPP switch.
Transfer case shift relays.
Transfer case mechanism.
Transmission range sensor.
GEM.
Digital transmission range (DTR) sensor

 

[bedrck46]

Measure the resistance between mode switch terminals 2 and 3 while rotating the mode switch through all positions; refer to the following chart:
Switch Position Resistance Range
2H 3705-4095 ohms
A4WD 1425-1575 ohms
4H 646-714 ohms
4L 228-252 ohms


Also check the brake switch it is possible that the circuit for the 4L could be the problem. the brake switch has two circuits that it controls

also check the shift relays

prints attached

 

[rockinrolla]

Will check today thanks

 

[bedrck46]

I was wrong about the brake switch the 98 switch only had one circuit for the switch should just be a light green and light green/red wire for the switch

 

[rockinrolla]

where do i connect the ohm meter to the selector wires? dark blue?

 

[bedrck46]

yes to the two dark blue wires

 

[rockinrolla]

I'm sorry I've been busy and I went out of town. The ohm readings were different every time I touched the wires, and it would only show the ohms for a second on each mode. Also I have to put it in neutral to engage 4 hi it would not engage in drive. Thanks for the help!

 

[bedrck46]

you need to disconnect the connector from the switch and read across pins 2 and 3 and read the ohms in each position

 

[rockinrolla]

I did that and it gave different readings each time on each section only showed for a sec.