Suzuki GRAND VITARA JB416, Service Manual

Page: 59 / 474

Engine General Information and Diagnosis: 1A-41
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?
Go to Step 13. 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.
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?
Go to Step 14. 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.
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?
Go to Step 15. Repair or replace
defective CAN
communication circuit.
15 Vehicle spec check
Is vehicle equipped with A/T?
Go to Step 16. Go to Step 17.
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?
Go to Step 17. Substitute a known-
good ECM and recheck.
Step Action Yes No