I have an '03 Ram 4x4 and noticed this spring that the 4x4 light was on while the shifter was in 2-wheel drive and went off when in 4x4. I took it out on a gravel road and shifted back and forth and spun the tires to make sure it was only the light and it seemed to correct it. Lately, I've notice the light will come on from time to time and I can just barely push the shifter towards 4x4 and it goes off. Seems a little backwards but that's what it takes. Has anyone seen this before? Seems like a short or switch somewhere. Can someone tell me how to fix it?

 

There is a part called "position sensor", cost about 32 bucks. It controls the light in the dash. Check the connector berfore you buy a replacement. My situation was no light and it took me 15 minutes to replace. The sensor goes in the front of the transfer case. Make sure the oil ring is reinstalled. The sensor replacement is not uncommon.

Hope it is something simple.

 

This problem went away shortly after I posted but now it's back. I took it out today and shifted the transfer case and eventually got the light to go out. Now the problem is it doesn't turn on at all! Can you tell me where the position sensor is located?

 

FROM THE SERVICE MANUAL, Page 21-443

POSITION SENSOR
DESCRIPTION
The transfer case position sensor is an electronic
device whose output can be interpreted to indicate
the transfer case’s current operating mode. The sensor
consists of a five position, resistive multiplexed
circuit which returns a specific resistance value to
the Powertrain Control Module (PCM) for each transfer
case operating mode. The sensor is located on the
top of the transfer case, just left of the transfer case
centerline and rides against the sector plate roostercomb.
The PCM supplies 5VDC (+/- 0.5V) to the sensor
and monitors the return voltage to determine the
sector plate, and therefore the transfer case, position.
OPERATION
During normal vehicle operation, the Powertrain
Control Module (PCM) monitors the transfer case
position sensor return voltage to determine the operating
mode of the transfer case. Refer to the Operating
Mode Versus Resistance table for the correct
resistance for each position (Fig. 87).

OPERATING MODE VERSUS RESISTANCE
SENSOR POSITION OPERATING MODE SENSOR RESISTANCE (ohms)
1 2H 1124-1243
2 4H 650-719
3 NEUTRAL 389-431
4 4L 199-221
5 NOT USED 57-64
REMOVAL
(1) Raise and support the vehicle.
(2) Disengage the transfer case position sensor
connector from the position sensor.
(3) Remove the position sensor from the transfer
case.
INSTALLATION
(1) Inspect the o-ring seal on the transfer case
position sensor. Replace the o-ring if necessary.
(2) Install the transfer case position sensor into
the transfer case. Torque the sensor to 20-34 N·m
(15-25 ft.lbs.).
(3) Engage the transfer case position sensor connector
to the position sensor.
(4) Lower vehicle.
(5) Verify proper sensor operation.
Fig. 87 Position Sensor Linear Movement
1 - POSITION 1 - 10mm ±0.5mm
2 - POSITION 2 - 12mm ±0.5mm
3 - POSITION 3 - 14mm ±0.5mm
4 - POSITION 4 - 16mm ±0.5mm
5 - POSITION 5 - 18mm ±0.5mm
6 - POSITION 6 - 20mm±0.5mm - FULL EXTENSION

 

Thanks! This is great feedback. Do you know if it can do any damage driving it the way it is? I assume it's alright since I have a manual shifter and not a push button. Thanks again.

 

Also, you wouldn't happen to have some kind of part number would you? I've looked all over the net and can't seem to find any. I do see speed sensors and throttle senors but not a transfer case position sensor.