Downloaded from www.Manualslib.com manuals search engine 10C-16 Immobilizer Control System:
DTC P1638: Immobilizer Information MismatchedS6RW0DA304017
Wiring Diagram
Refer to “Immobilizer Control System Wiring Circuit Diagram”.
Detecting Condition and Trouble Area
Troubleshooting4CAN communication circuit check
1) Disconnect connectors from ECM, BCM and ABS
control module.
2) Check CAN communication circuit for open, short and
high resistance.
• Between ECM and ABS control module
• Between BCM and ABS control module
Is each CAN communication circuit in good condition?Go to Step 5. Repair circuit.
5Replacement of BCM
1) Replace BCM with new one referring to “BCM (Included
in Junction Block) Removal and Installation in Section
10B”.
2) Check ECM for DTC referring to “DTC Check”.
Is DTC P1636 still detected?Substitute a known-
good ECM and recheck.BCM faulty. Step Action Yes No
Detecting Condition Trouble Area
• The immobilizer control system information in ECM and
the one in BCM does not match.
• The registration of the immobilizer control system
information in ECM is failed.• Use of the wrong ECM
• CAN communication circuit
• Keyless start control module (if equipped)
• Combination meter
• TCM (A/T model)
• 4WD control module (if equipped)
• ABS control module
•BCM
•ECM
Step Action Yes No
1Was “Immobilizer Control System Check” performed?Go to Step 2. Go to “Immobilizer
Control System Check”.
2DTC confirmation
1) Disconnect negative (–) cable from battery for more than
5 seconds.
2) Connect negative (–) cable to battery.
3) Check if any DTC is detected referring to “DTC Check”.
Is DTC P1638 still detected?Go to Step 3. Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”.
3ECM specification check
1) Check ECM part number to see if ECM is applicable to
the vehicle in service.
Is a correct ECM used for the vehicle in service?Go to Step 4. Replace ECM with the
correct one and recheck
if DTC P1638 is still
detected by ECM.
4DTC check of ECM
1) Check ECM for DTC referring to “DTC Check in Section
1A”.
Is DTC U0073, U0101, U0121 and/or U0140 detected?Go to applicable DTC
diag. flow.Go to Step 5.
Downloaded from www.Manualslib.com manuals search engine Immobilizer Control System: 10C-17
Inspection of ICM and Its CircuitS6RW0DA304018
ICM and its circuit can be checked at ICM wiring connector by measuring voltage.
CAUTION!
ICM cannot be checked by itself. It is strictly prohibited to connect voltmeter or ohmmeter to ICM with
connector disconnected from it.
Voltage Check
1) Remove ICM (1) from steering lock assembly or steering lock unit referring to “ICM Removal and Installation”.
2) Connect ICM connector (2) to ICM.
3) Check voltage at each terminal.
NOTE
As each terminal voltage is affected by the battery voltage, confirm that it is 11 V or more when the
ignition switch is turned to ON position.
5DTC check of BCM
1) Check BCM for DTC referring to “DTC Check in Section
10B”.
Is DTC U0073, U0100, U0101, U0155 and/or U1144
detected?Go to applicable DTC
diag. flow.Go to Step 6.
6CAN communication circuit check
1) Disconnect connectors from ECM, BCM and ABS
control module.
2) Check CAN communication circuit for open, short and
high resistance.
• Between ECM and ABS control module
• Between BCM and ABS control module
Is each CAN communication circuit in good condition?Go to Step 7. Repair circuit.
7Replacement of BCM
1) Replace BCM with new one referring to “BCM (Included
in Junction Block) Removal and Installation in Section
10B”.
2) Check ECM for DTC referring to “DTC Check”.
Is DTC P1638 still detected?Substitute a known-
good ECM and recheck.BCM faulty. Step Action Yes No
1 2 3
4
1
25
6 [A]
I6RW0BA30003-01
[A]: ICM connector (harness side view)
