DTC C1437: Lost Communication with ECM: Procedure

1. Using the Techstream, check for any momentary interruption in the wire harness and connector corresponding to the DTC. Refer to CHECK FOR INTERMITTENT PROBLEMS .
   MOMENTARY INTERRUPTION CHECK
   
   

   Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
   EFI Communication Open	EFI communication open detection / ERROR or NORMAL	ERROR: Momentary interruption NORMAL: Normal	-

   OK

   There are no momentary interruptions.

   HINT: 

   Perform the above inspection before removing the sensor and connector.

NG → See step   3 

OK: Go to next step 

1. Turn the engine switch off.
2. Clear the DTCs. Refer to DTC CHECK / CLEAR .
3. Start the engine.
4. Drive the vehicle at a speed of 15 km/h (9 mph) or more for 10 seconds or more.
5. Check that no CAN communication system DTC is output. Refer to DIAGNOSIS SYSTEM .
6. Check if the same DTC is recorded. Refer to DTC CHECK / CLEAR .

   Result

   Result	Proceed to
   DTC (C1437) is not output	A
   DTC (C1437) is output	B
   DTC (CAN communication system DTC) is output	C

C → See step   7 

B → See step   6 

A → See step   5 

1. Turn the engine switch off.
2. Repair or replace the harness or connector.
3. Check for any momentary interruption between the skid control ECU and the ECM. Refer to CHECK FOR INTERMITTENT PROBLEMS .
4. Check that there is no momentary interruption.

NEXT: Go to next step 

1. Turn the engine switch off.
2. Clear the DTCs. Refer to DTC CHECK / CLEAR .
3. Start the engine.
4. Drive the vehicle at a speed of 15 km/h (9 mph) or more for 10 seconds or more.
5. Check that no CAN communication system DTC is output. Refer to DIAGNOSIS SYSTEM .
6. Check if the same DTC is recorded. Refer to DTC CHECK / CLEAR .

   Result

   Result	Proceed to
   DTC (C1437) is not output	A
   DTC (C1437) is output	B
   DTC (CAN communication system DTC) is output	C

C → See step   7 

B → See step   6 

A → END