DTC U0001:88, U0073, U1900 [MULTIPLEX COMMUNICATION SYSTEM (L.H.D.)]

DTC	U0001:88	Module communication error
DETECTION CONDITION	Warning • Perform the following on-board diagnosis according to FOREWORD [MULTIPLEX COMMUNICATION SYSTEM (L.H.D.)] troubleshooting procedure. • CAN system-related harness malfunction • CAN system-related module malfunction
POSSIBLE CAUSE	• Open or short circuit in wiring harness • Malfunction of connectors between PCM, TCM, ABS HU/CM, DSC HU/CM, power retractable hardtop control module, active bonnet control module, keyless control module, steering angle sensor and instrument cluster • PCM malfunction • TCM malfunction • ABS HU/CM malfunction • DSC HU/CM malfunction • Power retractable hardtop control module malfunction • Active bonnet control module malfunction • Keyless control module malfunction • Steering angle sensor malfunction • Instrument cluster malfunction

DTC

U0001:88

Module communication error

U0073

Module communication error

U1900

CAN system communication error

DETECTION CONDITION

Warning

• Perform the following on-board diagnosis according to FOREWORD [MULTIPLEX COMMUNICATION SYSTEM (L.H.D.)] troubleshooting procedure.

• CAN system-related harness malfunction

• CAN system-related module malfunction

POSSIBLE CAUSE

• Open or short circuit in wiring harness

• Malfunction of connectors between PCM, TCM, ABS HU/CM, DSC HU/CM, power retractable hardtop control module, active bonnet control module, keyless control module, steering angle sensor and instrument cluster

• PCM malfunction

• TCM malfunction

• ABS HU/CM malfunction

• DSC HU/CM malfunction

• Power retractable hardtop control module malfunction

• Active bonnet control module malfunction

• Keyless control module malfunction

• Steering angle sensor malfunction

• Instrument cluster malfunction

Step	Inspection	Action
1	VERIFICATION BEFORE SERVICING • Are any DTCs, except the following, displayed? ― U0001:88 ― U0073 ― U1900	Yes	Determine the open circuit location referring to DETERMINING MALFUNCTIONING PART (HS-CAN) [MULTIPLEX COMMUNICATION SYSTEM (L.H.D.)].
No	Go to the next step.
2	INSPECTION OF CONTROL MODULE CONNECTOR OUTPUTTING DTCs • Inspect the terminal condition of the control module connector outputting DTCs and the mid-connector. • Are the connector terminals normal without damage, deformation, corrosion, or disconnection?	Yes	Go to the next step.
No	Repair or replace the connector, then go to Step 9.
3	INSPECTION OF POWER SUPPLY OF CONTROL MODULE OUTPUTTING DTCs • Refer to the terminal voltage table of the control module outputting DTCs or use the PID/data monitoring function to inspect the terminal voltage and fuse condition. • Is the power supply voltage normal?	Yes	Go to the next step.
No	Repair or replace the connector, then go to Step 9.
4	INSPECTION OF BODY GROUND CONDITION OF CONTROL MODULE OUTPUTTING DTCs • Inspect the body ground wires and ground point of the control module outputting DTCs. • Are the ground and ground point normal?	Yes	Go to the next step.
No	Repair or replace the connector, then go to Step 9.
5	CAN SYSTEM RELATED WIRING HARNESS INSPECTION • CAN system related wiring harness inspection: ― Short to ground ― Short to power supply ― Short between twisted pair wiring harness ― Open circuit • Is the wiring harness normal?	Yes	Go to the next step.
No	Repair or replace the connector, then go to Step 9.
6	INSPECT PCM • Disconnect the PCM connector. • Measure the resistance between the following PCM connector terminals: ― Between terminal 1AM and terminal 1AI (part side) • Is the resistance 118-130 ohms?	Yes	Go to the next step.
No	Replace the PCM, then go to Step 9. (See PCM REMOVAL/INSTALLATION [L8, LF].)
7	INSPECT INSTRUMENT CLUSTER • Disconnect the instrument cluster connector. • Measure the resistance between the following instrument cluster connector terminals: ― Between terminal 1J and terminal 1L (part side) • Is the resistance 118-130 ohms?	Yes	Go to the next step.
No	Replace the instrument cluster, then go to Step 9. (See INSTRUMENT CLUSTER REMOVAL/INSTALLATION.)
8	CAN RELATED MODULE VERIFICATION • Remove only one of the CAN-related modules. • Clear DTCs using the M-MDS. • Inspect the DTCs of all modules using the M-MDS. • Are DTCs U0001:88, U0073, U1900 displayed?	Yes	Reinstall the removed module, remove another module and perform the same inspection. Inspect all of the CAN-related modules using the same procedure. After inspecting all of the modules, go to the next step.
No	Replace the removed module.
9	AFTER REPAIR VERIFICATION • Connect all of the modules. • Clear DTCs using the M-MDS. • Inspect the DTCs using the M-MDS. • Are DTCs displayed?	Yes	Perform the CAN system on-board diagnosis again according to the troubleshooting procedure (See FOREWORD [MULTIPLEX COMMUNICATION SYSTEM (L.H.D.)].)
No	DTC troubleshooting completed.

Step

Inspection

Action

VERIFICATION BEFORE SERVICING

• Are any DTCs, except the following, displayed?

― U0001:88

― U0073

― U1900

Yes

Determine the open circuit location referring to DETERMINING MALFUNCTIONING PART (HS-CAN) [MULTIPLEX COMMUNICATION SYSTEM (L.H.D.)].

Go to the next step.

INSPECTION OF CONTROL MODULE CONNECTOR OUTPUTTING DTCs

• Inspect the terminal condition of the control module connector outputting DTCs and the mid-connector.

• Are the connector terminals normal without damage, deformation, corrosion, or disconnection?

Yes

Go to the next step.

Repair or replace the connector, then go to Step 9.

INSPECTION OF POWER SUPPLY OF CONTROL MODULE OUTPUTTING DTCs

• Refer to the terminal voltage table of the control module outputting DTCs or use the PID/data monitoring function to inspect the terminal voltage and fuse condition.

• Is the power supply voltage normal?

Yes

Go to the next step.

Repair or replace the connector, then go to Step 9.

INSPECTION OF BODY GROUND CONDITION OF CONTROL MODULE OUTPUTTING DTCs

• Inspect the body ground wires and ground point of the control module outputting DTCs.

• Are the ground and ground point normal?

Yes

Go to the next step.

Repair or replace the connector, then go to Step 9.

CAN SYSTEM RELATED WIRING HARNESS INSPECTION

• CAN system related wiring harness inspection:

― Short to ground

― Short to power supply

― Short between twisted pair wiring harness

― Open circuit

• Is the wiring harness normal?

Yes

Go to the next step.

Repair or replace the connector, then go to Step 9.

INSPECT PCM

• Disconnect the PCM connector.

• Measure the resistance between the following PCM connector terminals:

― Between terminal 1AM and terminal 1AI (part side)

• Is the resistance 118-130 ohms?

Yes

Go to the next step.

Replace the PCM, then go to Step 9.

(See PCM REMOVAL/INSTALLATION [L8, LF].)

INSPECT INSTRUMENT CLUSTER

• Disconnect the instrument cluster connector.

• Measure the resistance between the following instrument cluster connector terminals:

― Between terminal 1J and terminal 1L (part side)

• Is the resistance 118-130 ohms?

Yes

Go to the next step.

Replace the instrument cluster, then go to Step 9.

(See INSTRUMENT CLUSTER REMOVAL/INSTALLATION.)

CAN RELATED MODULE VERIFICATION

• Remove only one of the CAN-related modules.

• Clear DTCs using the M-MDS.

• Inspect the DTCs of all modules using the M-MDS.

• Are DTCs U0001:88, U0073, U1900 displayed?

Yes

Reinstall the removed module, remove another module and perform the same inspection. Inspect all of the CAN-related modules using the same procedure. After inspecting all of the modules, go to the next step.

Replace the removed module.

AFTER REPAIR VERIFICATION

• Connect all of the modules.

• Clear DTCs using the M-MDS.

• Inspect the DTCs using the M-MDS.

• Are DTCs displayed?

Yes

Perform the CAN system on-board diagnosis again according to the troubleshooting procedure

(See FOREWORD [MULTIPLEX COMMUNICATION SYSTEM (L.H.D.)].)

DTC troubleshooting completed.