7.18
FINAL DRIVE
AWD Diagnosis
Symptom: AWD Will Not Engage
1. Check the gearcase coil resistance. To test the coil
resistance, measure between the Grey and Brown/White
wires. The measurement should be within specification.
2. Turn the ignition and AWD switches on and place gear
selector in High or Low gear. Check for minimum battery
voltage at the Gray and Brown/White chassis wires that
power the coil. A minimum of 11 Vdc should be present.
3. If electrical tests are within specification, remove gearcase
(see “Gearcase Removal”) and inspect components.
4. Inspect the armature plate for a consistent wear pattern.
There should be two distinct wear bands (one band inside
the other). If only one band of wear is present (or if there
is wear between the two bands), inspect the coil area as
indicated in Step 5. A wear band with an interrupted wear
mark may indicate a warped plate, which may cause
intermittent operation. See the following illustrations:
5. Check to make sure the coil is seated in the U-shaped insert
that is pressed into the gearcase cover. The top of the coil
should be seated below the U-shaped insert. The U-shaped
insert controls the pole gap. If the top of the coil is above
the surface of the U-shaped insert it raises the armature
plate, thereby increasing pole gap. If the pole gap increases
the coil will not be strong enough to engage the AWD
system. If this is found, replace the cover plate assembly.
6. Inspect the rollers for nicks and scratches. The rollers must
slide up, down, in and out freely within the roll cage sliding
surfaces and H-springs.
7. Inspect the roll cage assembly for cracks or excessive wear.
If damaged, replace the roll cage assembly.
Front Gearcase Coil Resistance:
21.6 - 26.4 Ohms
Check for
Armature Plate
wear bands
Gearcase Cover Plate Asm.
Coil
U-shaped insert
Side cutaway
view of cover
Rollers
Roll Cage Assembly
www.midwestmanuals.com www.green-manuals.com
To Next Page
Loading...
Need help?
General
