B1602
DTC B1602 CAN ERRORComponent Location:
GENERAL DESCRIPTION
The 6 components related with Body Control Module(hereinafter referred to BCM) connect with each other via CAN(Controller Area Network) communication system. These are BCM. Assist Door Module (ADM), Drive Door Module (DDM), Power Seat Unit (PS), tilt/telescope control unit and Personal Identification Card (PIC).
Wiper Motor Module (WMM) and Multi-Function Switch (M/F) connect with BCM via LIN (Local Interconnect Network) Therefore it is possible to diagnose an overall system with scantool.
*1 CAN (Cotroller Area network) : CAN is a serial bus system especially suited for networking "intelligent" devices as well as sensors and actuators within a system or sub-system.
*2 LIN (Local Interconnect Network) : LIN is a new low cost serial communication system intended to be used for distributed electronic systems in vehicles, which complements the existing portfolio of automotive multiplex networks.
DTC DESCRIPTION
This code is set if IC in the control module detects the following error although an communication condition is normal; CANH wire interrupted, CANL wire interrupted, CANH short-circuited to battery, CANH short-circuited to ground CANH short-circuited to ground, CANL short-circuited to battery, CANL and CANH mutually short-circuited.
DTC Detecting Condition:
Schematic Diagram:
Signal Waveform And Data:
MONITOR SCANTOOL DATA
1. Ignition "OFF", connect scantool.
2. Ignition "ON" & Engine "OFF", select "Diagnostic Trouble Codes (DTC)" mode.
3. Monitor diagnostic trouble code and present of trouble code.
4. Using a scan tool, clear the DTC.
5. Are any DTC present?
YES - Go to "W/Harness Inspection" procedure.
NO
- Displaying nothing (no DTC) shows that Fault is intermittent caused by poor contact in the part's and/or BCM connector or was repaired and BCM memory was not cleared.
Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
- Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure.
TERMINAL AND CONNECTOR INSPECTION
1. Many malfunctions in the electrical system are caused by poor harness(es) and terminals. Faults can also be caused by interference from other electrical systems and mechanical or chemical damage.
2. Check the following conditions:
1. Check for damaged harness and terminals: contact resistance, oxidation, bent or broken terminals.
2. Check for poor connection between ECM and component: backed out terminal, improper mating, broken locks and poor terminal to wire connection.
NOTE: Using a suitable male pin to ensure that contact in sockets is good. The pin should remain in position when pulled gently.
3. Has a problem been found?
YES - Repair as necessary and then go to "Verification of Vehicle Repar" procedure.
NO - Go to "BCM Signal Circuit Inspection" procedure.
BCM SIGNAL CIRCUIT INSPECTION
1. Check CAN high communication circuit
1. Ignition "ON" and Engine "OFF"
2. Connect scantool and select VEHICLE SCOPEMETER function
3. Measure waveform between "CAN high" of BCM connector and chassis ground.
Specification : If CAN high communication waveform is displayed, it is OK.
4. Is CAN high communication waveform displayed within specification?
YES - Go to "Check CAN low communication circuit" as below.
NO - Repair the short to ground or battery in the CAN communication circuit and go to "Verification of Vehicle Repair".
2. Check CAN low communication circuit
1. Ignition "ON" and Engine "OFF"
2. Connect scantool and select VEHICLE SCOPEMETER function.
3. Measure waveform between "CAN Low" of BCM connector and chassis ground.
Specification : If CAN low communication waveform is displayed, it is OK
4. Is CAN communication waveform displayed within specification?
YES - Go to "Component Inspection" procedure.
NO - Repair the short to ground or battery or CAN high communication circuit and go to "Verification of Vehicle Repair".
COMPONENT INSPECTION
1. Check CAN communication ECU's internal error
1. Ignition "ON" and engine "OFF".
2. Connect scantool and select DIAGNOSIS TROUBLE CODE.
3. Monitor that DTC is cleared by disconnecting of the ECU's* harness connector one by one.
*ECU's : BCM, power window main switch, power window assist switch, power seat ECU, tilt/telescope control unit, PIC (Personal Identification Card) ECU.
4. Is CAN ERROR DTC cleared?
YES - Substitute with a known-good one of them and check proper condition.
If the problem is corrected, replace one of them and then go to "Verification of Vehicle Repair" procedure.
NO - Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration or damage.
Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure.
VERIFICATION OF VEHICLE REPAIR
After a repair, it is essential to verify that the fault has been corrected.
1. Connect scan tool and select "Diagnostic Trouble Codes (DTC)" mode.
2. Using a scan tool, clear the DTC.
3. Operate the vehicle within DTC Enable conditions in General information.
4. Are any DTC present?
YES - Go to the applicable troubleshooting procedure.
NO - System performing to specification at this time.