Suzuki Grand Vitara JB416 / JB420 (ESP model). Service manual - part 11

1A-40 Engine General Information and Diagnosis:

DTC P1678: CAN Communication (Reception Error for BCM)

S5JB0E1104066

Wiring Diagram
Refer to “DTC P1674: CAN Communication (Bus Off Error)”.

DTC Detecting Condition and Trouble Area

DTC Confirmation Procedure

1) Connect scan tool to DLC with ignition switch turned OFF.
2) Turn ON ignition switch and clear DTC by using scan tool.
3) Start engine and run it for 1 min. or more.
4) Check DTC.

DTC Troubleshooting

NOTE
Before this trouble shooting is performed, read the precautions for DTC troubleshooting referring to
“Precautions For DTC Troubleshooting in related manual”.

DTC detecting condition

Trouble area

Reception error of communication data for BCM is
detected for longer than specified time continuously.
(1 driving detection logic but MIL does not light up)

• ECM
• BCM
• CAN communication line circuit

Step

Action

Yes

Was “Engine and Emission Control System Check”
performed?

Go to Step 2.

Go to “Engine and
Emission Control
System Check in related
manual”.

DTC check
1) Connect scan tool to DLC with ignition switch turned

OFF.

2) Check ECM, TCM (for A/T model), ABS / ESP

® control

module, 4WD control module (if equipped), keyless start
control module (if equipped) and BCM for DTC.

Is there any DTC(s) other than CAN communication DTC(s)
at each control module (other than DTC P1618, P1674,
P1676, P1678, P1685 in ECM, DTC P1774, P1777, P1778
in TCM (for A/T model), DTC U1073, U1100, U1101, U1121,
U1126, U1139, U1140, U1144 in BCM, ABS / ESP

control

module and 4WD control module (if equipped), and DTC
No.31 / 33 in keyless start control module (if equipped))?

Go to applicable DTC
diag. flow.

Go to Step 3.

CAN communication error check for ECM
1) Check ECM for DTC.

Is there DTC P1674?

Go to “DTC P1674:
CAN Communication
(Bus Off Error)”.

Go to Step 4.

ECM, ABS / ESP

® control module and BCM connector

check
1) Check for proper connection at each ECM, ABS / ESP

control module and BCM connector terminals with
ignition switch turned OFF.

2) If connections are OK, recheck ECM for DTC with

engine running.

Is there DTC P1678?

Go to Step 5.

Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section 00
in related manual”.

Engine General Information and Diagnosis: 1A-41

ECM power and ground circuit check
1) Check ECM power and ground circuits referring to “ECM

Power and Ground Circuit Check in related manual”.

Are they in good condition?

Go to Step 6.

Repair ECM power and/
or ground circuits.

DTC check in BCM
1) Check DTC U1073 in BCM.

Is it indicated?

Go to “DTC U1073 (No.
1073): Control Module
Communication Bus Off
in Section 10B”.

Go to Step 7.

CAN communication circuit check
1) Disconnect connectors from BCM and ECM.
2) Check that CAN communication circuit is as follows.

• Circuit resistance of CAN communication circuit is

less than 1

Ω between “WHT/RED” terminal of ECM

connector and “RED” terminal of BCM connector.

• Circuit resistance of CAN communication circuit is

less than 1

Ω between “WHT/BLU” terminal of ECM

connector and “WHT” terminal of BCM connector.

Is it in good condition?

Go to Step 9.

Go to Step 8.

ABS or ESP

® control module check

1) Measure resistance at following connector terminals.

• Between “WHT/BLU” terminal and “WHT” terminal of

ABS or ESP

® control module connector.

• Between “WHT/RED” terminal and “RED” terminal of

ABS or ESP

® control module connector.

Is measured resistance below 1

Ω

CAN communication
circuit wire between
BCM and ECM
connector is open or
high resistance.

Substitute a known-
good ABS or ESP

control module and
recheck.

DTC check
1) Connect connectors to BCM and ECM with ignition

switch turned OFF.

2) Disconnect connectors from TCM (for A/T model) with

ignition switch turned OFF.

3) Check ECM for DTC.

Is there DTC P1678?

Go to Step 10.

CAN communication
circuit wire between
TCM and CAN circuit
junction connector is
open or high resistance.
If wires are OK, check
TCM power and ground
circuits. If circuits are
OK, substitute a known-
good TCM (for A/T
model) and recheck.

10 DTC check

1) Disconnect connector from keyless start control module

(if equipped) with ignition switch turned OFF.

2) Check ECM for DTC.

Is there DTC P1678?

Go to Step 11.

CAN communication
circuit wire between
keyless start control
module and CAN circuit
junction connector is
open or high resistance.
If wires are OK, check
keyless start control
module power and
ground circuits. If
circuits are OK,
substitute a known-
good keyless start
control module and
recheck.

Step

Action

Yes

1A-42 Engine General Information and Diagnosis:

11 DTC check

1) Disconnect connector from combination meter with

ignition switch turned OFF.

2) Check ECM for DTC.

Is there DTC P1678?

Go to Step 12.

CAN communication
circuit wire between
combination meter and
CAN circuit junction
connector is open or
high resistance. If wires
are OK, check
combination meter
power and ground
circuits. If circuits are
OK, substitute a known-
good combination meter
and recheck.

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.

Step

Action

Yes

Engine General Information and Diagnosis: 1A-43

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.

17 Combination meter operation check

1) Check combination meter operation for seat belt warning

lamp by fastening and unfastening driver side seat belt
with ignition switch turned ON.

Is it check result satisfactory?

Substitute a known-
good ECM and recheck.

Check BCM power and
ground circuits, If
circuits are OK,
substitute a known-
good BCM and recheck.

Step

Action

Yes

Content .. 9 10 11 12 ..