B1591

B1591

Component Location:

General Description
To make system be more efficient, Body Control Module (here in after referred to BCM) applies CAN (Controller Area Network) communication system. CAN is a kind of communication system which can make related component share system information with just two line instead of complex individual signal line. It consists of related component and CAN BUS which consists of CAN_high line and CAN_low line. Each component can send and receive information by binary signal via CAN BUS. The related components for BCM are IPM, ADM, DDM, FAM, RAM, IMS and cluster module. Multifunction switch is submodule of IPM. It translates lamp, wiper, washer control signal from driver to IPM and according to this signal, IPM controls units

DTC Description
The ECM sets DTC B1590 if received turn signal of multifunction switch is invalid

DTC Detecting Condition:

Schematic Diagram:

Monitor Scantool Data
1. Connect scantool to Data Link Connector (DLC).
2. Ignition "ON" & engine "OFF"
3. Select "Diagnostic Trouble Codes (DTCs)" mode and monitor "DTC Status" parameter
4. Is the DTC B1591 present?

YES
a. Go to "Inspection & Repair" procedure

NO
a. Fault is intermittent caused by poor contact in the sensor's and/or ECM's connector or was repaired and ECM 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 and terminals.
Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3. Has a problem been found?

YES
a. Repair as necessary and go to "Verification Vehicle Repair" procedure

NO
a. Go to "W/Harness Inspection" procedure

Signal Circuit Inspection

Check for short in harness
1. Ignition "ON" and Engine "OFF" & turn signal switch "OFF"
2. Measure resistance between terminal "BCM-IM-13, 60" of IPM and chassis ground.

Specification :Infinity ohms






3. Is the measured resistance within specifications?

YES
a. Go to "Component Inspection" procedure.

NO
a. Check for short in signal harness. Repair as necessary and go to "Verification of Vehicle Repair" procedure.

Component Inspection

Check Multifunction switch
1. Connect scantool to Data Link Connector (DLC).
2. Ignition "ON" & engine "OFF"
3. Check combination of turn signal signal while operating turn signal switch

Specification : left turn -> L/TURN SIGNAL 'ON' & R/TURN SIGNAL 'OFF' right turn -> L/TURN SIGNAL 'OFF' & R/TURN SIGNAL 'ON'






4. Is the measured current data within specifications?

YES
a. Go to "Check IPM" procedure.

NO
a. Substitute with a known-good multifunction switch and check for proper operation. If the problem is corrected, replace multifunction switch and then go to "Verification of Vehicle Repair" procedure.

Check IPM
5. Connect scantool to Data Link Connector (DLC).
6. Ignition "ON" & engine "OFF"
7. Substitute with a known-good IPM and Check if the DTC is erased
8. Is the DTC erased?

YES
a. Substitute with a known-good IPM and check for proper operation.
If the problem is corrected, replace IPM and then go to "Verification of Vehicle Repair" procedure.

NO
a. 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 scantool and select "Diagnostic Trouble Codes (DTCs)" mode and then clear DTC
2. Operate the vehicle and monitor the DTC on the scantool
3. Are any DTCs present?

YES
a. Go to the applicable troubleshooting procedure

NO
a. System is performing to specification at this time.