Suzuki Grand Vitara XL-7 Service Manual page 537

7E-6 DIFFERENTIAL (FRONT)
4WD CONTROL SYSTEM DIAGNOSTIC FLOW TABLE
Before performing the trouble diagnosis, check that the transfer and front differential are in good condition.
[NOTES ON SYSTEM CIRCUIT INSPECTION]
D Be sure to read "PRECAUTIONS FOR ELECTRICAL CIRCUIT SERVICE" in Section 0A before circuit inspection
and observe what is written there.
D For system circuit, refer to the figure of "GENERAL DESCRIPTION" in this section.
D For terminal arrangement, refer to "4WD CONTROL CIRCUIT INSPECTION" in this section.
Step
1 Inspect 4WD control system for air leakage and
operation referring to "4WD CONTROL SYSTEM"
of "ON-VEHICLE SERVICE" in this section.
Is the result OK?
2 Inspect actuator for air leakage and operation
referring to "ACTUATOR" of "ON-VEHICLE
SERVICE" in this section.
Is the result OK?
3 Inspect air pump assembly for air leakage and
operation referring to "AIR PUMP ASSEMBLY" of
"ON-VEHICLE SERVICE" in this section.
Is the result OK?
4 Check ground circuit.
1) Disconnect connector from 4WD controller with
ignition switch OFF.
2) Check for proper connection to 4WD controller
at all terminal.
3) If OK, Check continuity between terminal E23-6
and body ground.
Is there continuity between terminal E23-6 and
body ground?
5 Check power circuit.
1) Disconnect connector from 4WD controller.
2) Turn ignition switch ON.
3) Check voltage between terminal E23-2 and
ground.
Is it 10 – 14 V?
6 Check 4WD switch circuit.
1) Connect coupler to 4WD controller.
2) Turn ignition switch ON and check voltage
between terminal E23-4 and ground.
Transfer lever is in "N" or "2H": 6 – 8 V
Transfer lever is in "4L" or "4H": 0 – 1 V
Action Yes
Go to Step 2.
4WD control system
and actuator are OK.
Recheck transfer and
front differential.
Go to Step 4.
Go to Step 5.
Go to Step 6.
Go to step 7.
No
Inspect for air leakage
from air hoses.
If OK, go to Step 3.
Inspect for air leakage
from air hoses.
If OK, inspect
differential assembly
referring to Section 7E
in UNIT REPAIR
MANUAL.
Replace air pump
assembly.
"BLK" wire is open.
"BLK/WHT" circuit is
open or short.
Check 4WD switch
(refer to Section 7A2),
"BLK/ORN" and "BLK"
circuit of 4WD switch.
If OK, substitute a
known-good 4WD
controller and recheck.