TCS

C1700

Component Location:

General Description
A special coding by means of a vehicle specific contact bridge in the cable harness = pin coding provides verification capability of compliance between vehicle and parameter setting. The stored parameter setting and the contact bridge are rechecked with each power-on or software reset.

DTC Description
The voltage at the ignition line is monitored via a comparator. A failure is detected if the voltage stays below the comparator threshold longer than the specified min. fault duration.

DTC Detecting Condition:

Schematic Diagram:

Terminal and Connector Inspection
1. Many malfunctions in the electrical system are caused by poor harness (es) and terminal condition. 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 - Repair as necessary and then go to "Verification of Vehicle Repair" procedure.

NO - Go to "Signal circuit inspection" procedure.

Signal Circuit Inspection
1. Ignition "OFF".
2. Disconnect HECU connector.
3. Measure resistance between terminal "14" of the HECU harness connector and terminal "9,38" of the HECU harness connector. (In case of ESC)

Specification : Approx. below 1 ohm






4. Is the measured resistance within specifications?

YES - Go to "Component Inspection" procedure.

NO - Check for open or short to GND in pin coding harness. Repair as necessary and then go to "Verification of Vehicle Repair" procedure.

Component Inspection
1. Ignition "OFF".
2. Ignition "ON".
3. Connect scantool and select "Diagnostic Trouble Codes (DTCs)" mode
4. Using a scantool, Clear DTC.
5. Select "Diagnostic Trouble Codes (DTCs)" mode again.
6. Are any DTCs present?

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

NO - Fault is intermittent caused by faulty HECU or was repaired and HECU memory was not cleared. 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 (DTCs)" mode
2. Using a Scantool, Clear DTC.
3. Operate the vehicle within DTC Detecting Condition in General Information.
4. Are any DTCs present?

YES - Go to the applicable troubleshooting procedure.

NO - System performing to specification at this time.