CODE No. C2332 Master-Slave communication fail


caution Before replacing the ECU, ensure that the power supply circuit, the earth circuit and the communication circuit are normal.

OPERATION


The BSW-ECU (master) communicates with the BSW-ECU (slave) through the local CAN lines.

CHECK CONDITION


When all of the conditions below are satisfied:

DIAGNOSTIC FUNCTION AND JUDGEMENT CRITERIA


When the BSW-ECU (master) cannot receive any CAN signal from the BSW-ECU (slave) for at least 1 second, the ECU will set diagnosis code No.C2332.

PROBABLE CAUSES



DIAGNOSIS PROCEDURE


STEP 1. M.U.T.-III CAN bus diagnostics


Use the M.U.T.-III to diagnose the CAN bus lines.

Q. Is the check result normal?

Go to Step 2.

Repair the CAN bus line (Refer to GROUP 54C - Troubleshooting ).

STEP 2. Resistance measurement at BSW-ECU (slave) connector terminal GND.


(1)Disconnect the connector, and measure at the wiring harness side.
(2)Measure the resistance between the BSW-ECU (slave) connector terminal GND and body earth.
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?

Go to Step 3

Repair the connector(s) or wiring harness.

STEP 3. Voltage measurement at BSW-ECU (slave) connector terminal IG.


(1)Disconnect the connector, and measure at the wiring harness side.
(2)Turn the ignition switch from the LOCK (OFF) position to the ON position.
(3)Check the voltage between the BSW-ECU (slave) connector terminal IG and body earth.
OK: System voltage

Q. Is the check result normal?

Go to Step 4

Repair the connector(s) or wiring harness.

STEP 4. Check of short and open circuit in CNH2 and CNL2 line between BSW-ECU (master) connector and BSW-ECU (slave) connector


(1)Disconnect the connector, and measure at the wiring harness side.
(2)Measure the resistance between the BSW-ECU (master) connector terminal CNH2 and the BSW-ECU (slave) connector terminal CNH2, and between the BSW-ECU (master) connector terminal CNL2 and the BSW-ECU (slave) connector terminal CNL2.
OK: Continuity exists (2 Ω or less)
(3)Measure the resistance between the BSW-ECU (master) connector terminal CNH2 and body earth, and between the BSW-ECU (master) connector terminal CNL2 and body earth.
OK: No continuity
(4)Measure the resistance between the BSW-ECU (master) connector terminal CNH2 and any of the other terminals, and between the BSW-ECU (master) connector terminal CNL2 and any of the other terminals.
OK: No continuity

Q. Is the check result normal?

Go to Step 5

Repair the connector(s) or wiring harness.

STEP 5. Measure the terminal resistance at the BSW-ECU.


caution A digital multimeter should be used. For details refer to .
(1)Remove the BSW-ECU (master/slave), and measure at the equipment side.
(2)Resistance between the BSW-ECU (master) connector terminal CNH2 and CNL2.
OK: 120 ± 20 Ω
(3)Resistance between the BSW-ECU (slave) connector terminal CNH2 and CNL2.
OK: 120 ± 20 Ω

Q. Is the check result normal?

Go to Step 6

Replace a defective ECU.

STEP 6. Check whether the diagnosis code is set again.


Check again if the diagnosis code is set in the BSW-ECU (master).
(1)Erase the diagnosis code.
(2)Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
(3)Check if diagnosis code is set.

Q. Is the diagnosis code set?

Replace the BSW-ECU (slave). Then Go to Step 7.

Intermittent malfunction is suspected (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to cope with Intermittent Malfunction).

STEP 7. Check whether the diagnosis code is set again.


Check again if the diagnosis code is set in the BSW-ECU (master).
(1)Erase the diagnosis code.
(2)Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
(3)Check if diagnosis code is set.

Q. Is the diagnosis code set?

Use the BSW-ECU (slave), which has been removed at step 6, as the BSW-ECU (master).

This diagnosis is complete.