Suzuki GRAND VITARA JB416 Service Manual page 59

Step
12 DTC check
1) Disconnect connector from 4WD control module (if
equipped) with ignition switch turned OFF.
2) Check ECM for DTC.
Is there DTC P1678?
13 DTC check
1) Disconnect connector from steering angle sensor
(vehicle with ESP®) with ignition switch turned OFF.
2) Check ECM for DTC.
Is there DTC P1678?
14 CAN communication circuit check
1) Disconnect connectors from all control modules (ECM,
TCM (if equipped), BCM, ABS or ESP® control module,
4WD control module (if equipped), keyless start control
module (if equipped), combination meter, steering angle
sensor (vehicle with ESP®) with ignition switch turned
OFF.
2) Check that CAN communication circuit is as follows.
• All wire harness resistance of CAN communication
circuit is less than 1 Ω between each control module.
• Insulation resistance between CAN communication
circuit wires is infinity at each control module
connector.
• Insulation resistance between each CAN
communication circuit wire and vehicle body ground is
infinity at each control module connector.
• Circuit voltage of CAN communication circuit is 0 V
with ignition switch turned ON.
Are they in good condition?
15 Vehicle spec check
Is vehicle equipped with A/T?
16 DTC check in TCM (for A/T model)
1) Connect connectors to all control modules with ignition
switch turned OFF.
2) Check DTC P1778 in TCM (for A/T model).
Is it indicated?
Action
Engine General Information and Diagnosis:
Yes
Go to Step 13.
Go to Step 14.
Go to Step 15.
Go to Step 16.
Go to Step 17.
1A-41
No
CAN communication
circuit wire between
4WD control module
and CAN circuit junction
connector is open or
high resistance. If wires
are OK, check 4WD
control module power
and ground circuits. If
circuits are OK,
substitute a known-
good 4WD control
module and recheck.
CAN communication
circuit wire between
steering angle sensor
and CAN circuit junction
connector is open or
high resistance. If wires
are OK, check steering
tangle sensor power
and ground circuits. If
circuits are OK,
substitute a known-
good steering angle
sensor and recheck.
Repair or replace
defective CAN
communication circuit.
Go to Step 17.
Substitute a known-
good ECM and recheck.