INSPECTION PROCEDURE 1: Communication between MUT-II/III and the ABS-ECU is not possible.

CIRCUIT OPERATION

The diagnostic output is made from the ABS-ECU (terminal 13) to the diagnosis output terminal (terminal 7) of the diagnosis connector.

When the diagnosis connector's diagnosis test mode control terminal (terminal 1) is grounded, the ABS-ECU (terminal 4) will go into diagnosis mode.

TECHNICAL DESCRIPTION (COMMENT)

When communication with the MUT-II/III is not possible, the cause is probably an open circuit in the ABS-ECU power circuit or an open circuit in the diagnostic output circuit.

TROUBLESHOOTING HINTS (THE MOST LIKELY CAUSES FOR THIS CASE:)

Blown fuse

Damaged wiring harness or connector

Malfunction of the hydraulic unit (Integrated with ABS-ECU)

DIAGNOSIS

STEP 1. Measure the voltage at ABS-ECU connector B-03.

Disconnect ABS-ECU connector B-03 and measure at the harness side.

Start the engine.

Measure the voltage between terminal 20 and earth.

OK: System voltage

Q: Is the check result normal?

YES: Go to Step 3

.
NO: Go to Step 2

STEP 2. Check the harness wire between the ignition switch (IG2) connector C-303 terminal 4 and ABS-ECU connector B-03 terminal 20.

NOTE: After inspecting the intermediate connector C-106, C-202, and C-203, inspect the wire. If the intermediate connector C-106, C-202 or C-203 is damaged, repair or replace it. Then go to Step 5

Q: Is the harness wire between the ignition switch (IG2) connector C-303 terminal 4 and ABS-ECU connector B-03 terminal 20 damaged?

YES: Repair it and go to Step 5

.
NO: Go to Step 5

STEP 3. Check the harness wires between ABS-ECU connector B-03 (terminals 4 and 13) and diagnosis connector C-23 (terminals 1 and 7).

NOTE: After inspecting intermediate connectors C-02, C-104 and C-105, inspect the wires. If the intermediate connector C-02, C-104 or C-105 is damaged, repair or replace it. Then go to Step 5

Q: Is any of the harness wires between ABS-ECU connector B-03 (terminals 4 and 13) and diagnosis connector C-23 (terminals 1 and 7) damaged?

YES: Repair it and go to Step 5

.
NO: Go to Step 4

STEP 4. Check the harness wires between ABS-ECU connector B-03 (terminals 2 and 18) and earth.

Q: Is any of the harness wires between ABS-ECU connector B-03 (terminals 2 and 18) and earth damaged?

YES: Repair it and then go to Step 5

.
NO: Check the troubleshooting condition. To reproduce the troubleshooting state replace the hydraulic unit (integrated with ABS-ECU).Then go to Step 5

. If the state of failure is not reproduced then a intermittent malfunction is suspected. Refer to GROUP 00, How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction

STEP 5. Retest the system.

Q: Does the MUT-II/III communicate with the ABS system?

YES: The procedure is complete.
NO: Return to Step 1


INSPECTION PROCEDURE 1: Communication between MUT-II/III and the ABS-ECU is not possible.

CIRCUIT OPERATION The diagnostic output is made from the ABS-ECU (terminal 13) to the diagnosis output terminal (terminal 7) of the diagnosis connector. When the diagnosis connector's diagnosis test mode control terminal (terminal 1) is grounded, the ABS-ECU (terminal 4) will go into diagnosis mode.
TECHNICAL DESCRIPTION (COMMENT) When communication with the MUT-II/III is not possible, the cause is probably an open circuit in the ABS-ECU power circuit or an open circuit in the diagnostic output circuit.
TROUBLESHOOTING HINTS (THE MOST LIKELY CAUSES FOR THIS CASE:) Blown fuse Damaged wiring harness or connector Malfunction of the hydraulic unit (Integrated with ABS-ECU)
	DIAGNOSIS

	STEP 1. Measure the voltage at ABS-ECU connector B-03. Disconnect ABS-ECU connector B-03 and measure at the harness side. Start the engine. Measure the voltage between terminal 20 and earth. OK: System voltage Q: Is the check result normal? YES: Go to Step 3 . NO: Go to Step 2.
	STEP 2. Check the harness wire between the ignition switch (IG2) connector C-303 terminal 4 and ABS-ECU connector B-03 terminal 20. NOTE: After inspecting the intermediate connector C-106, C-202, and C-203, inspect the wire. If the intermediate connector C-106, C-202 or C-203 is damaged, repair or replace it. Then go to Step 5 . Q: Is the harness wire between the ignition switch (IG2) connector C-303 terminal 4 and ABS-ECU connector B-03 terminal 20 damaged? YES: Repair it and go to Step 5. NO: Go to Step 5.
	STEP 3. Check the harness wires between ABS-ECU connector B-03 (terminals 4 and 13) and diagnosis connector C-23 (terminals 1 and 7). NOTE: After inspecting intermediate connectors C-02, C-104 and C-105, inspect the wires. If the intermediate connector C-02, C-104 or C-105 is damaged, repair or replace it. Then go to Step 5 . Q: Is any of the harness wires between ABS-ECU connector B-03 (terminals 4 and 13) and diagnosis connector C-23 (terminals 1 and 7) damaged? YES: Repair it and go to Step 5. NO: Go to Step 4.
	STEP 4. Check the harness wires between ABS-ECU connector B-03 (terminals 2 and 18) and earth. Q: Is any of the harness wires between ABS-ECU connector B-03 (terminals 2 and 18) and earth damaged? YES: Repair it and then go to Step 5 . NO: Check the troubleshooting condition. To reproduce the troubleshooting state replace the hydraulic unit (integrated with ABS-ECU).Then go to Step 5. If the state of failure is not reproduced then a intermittent malfunction is suspected. Refer to GROUP 00, How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction.
	STEP 5. Retest the system. Q: Does the MUT-II/III communicate with the ABS system? YES: The procedure is complete. NO: Return to Step 1 .