C1611 CAN Time-out ECM - Automotive Diagnosis

COMPONENT LOCATION

GENERAL DESCRIPTION

EPS provides a different assist force according to vehicle speed when engine ON. EPS CM receives engine condition and vehicle speed from ECM as EMS1 signal.

DTC DESCRIPTION

EPS CM sets this code if EMS1 message is not received within predefined time.

DTC DETECTING CONDITION

Item

Detecting Condition

Possible cause

DTC Strategy

Check EMS1 message time interval.

Open or short in CAN harness of engine side

Faulty ECM

Enable conditions

–

Threshold value

EMS 1 message isn’t received for more than 3s.

Fail Safe

EPS CM sets vehicle speed as 80kph (50mile).

Restoration conditions

EMS 1 message is received for more than 1s.

DIAGNOSTIC CIRCUIT DIAGRAM

MONITOR SCANTOOL DATA

1.	Connect scantool to Data Link Connector(DLC)

2.	Ignition “ON” & Engine “ON”.

3.	Monitor the “VEHICLE SPEED SENSOR” parameters on the Scantool.

4.	Drive the vehicle approx watching the speedometer on the instrument panel. Fig.1) Stand Still (IG ON & ENG ON)

Is parameter within specifications?

	▶ Fault is intermittent and caused either by poor contact in connectors or wiring harness, or it has been repaired and EPS CM memory is not cleared yet. Thoroughly check all connectors (and connections) for looseness, bending, corrosion, contamination, deterioration, and/or damage. Repair or replace as necessary
	▶ Go to “W/Harness Inspection” 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 all connectors (and connections) for looseness, bending, corrosion, contamination, deterioration, and/or damage.

Has a problem been found ?

	▶ Repair as necessary
	▶ Go to “CAN Circuit Inspection” procedure.

CAN CIRCUIT INSPECTION (EPS ↔ ECM)

■ Open Check

1.	Ignition “OFF”.

2.	Disconnect EPS CM & ECU connector .

3.	Measure resistance between CAN HIGH terminal of the EPS CM harness connector and CAN HIGH terminal terminal of the ECM harness connector.

Measure resistance between CAN LOW terminal of the EPS CM harness connector and CAN LOW terminal terminal of the ECM harness connector.

Approx. below 1Ω

Is the measured resistance within specifications?

	▶ Go to “Component Inspection” procedure.
	▶ Check Open between EPS CM & engine ECU harness. Repair as necessary

COMPONENT INSPECTION

1.	Ignition “OFF”.

2.	Ignition “ON” & Engine “OFF”.

3.	Connect scantool and select “Diagnostic Trouble Codes(DTCs)” mode

4.	Using a scantool, Clear DTC.

5.	Select “Diagnostic Trouble Codes(DTCs)” mode again.

Are any DTCs present ?

	▶ Substitute with a known-good PCM(ECM) and check for proper operation. If problem is corrected, replace PCM(ECM) . If NG, replace steering column & EPS unit assembly
	▶ Fault is intermittent and caused either by poor contact in connectors or wiring harness, or it has been repaired and EPS CM memory is not cleared yet.

New Videos on our YouTube Channel Every Week, Subscribe Now!