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Diagnostic Procedure

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ENGINE DOES NOT RESTART (PYUL) DIAGNOSTIC PROCEDURE

Step Inspection Results Action
1 VERIFY ENGINE CRANKING OCCURRENCE 
  • Start the engine.
  • Does the engine start?
Yes Go to the next step.
No Perform the symptom troubleshooting [WILL NOT CRANK] and [CRANKS NORMALLY BUT WILL NOT START].
(See WILL NOT CRANK [PYUL] .)
(See CRANKS NORMALLY BUT WILL NOT START [PYUL] .)
2 VERIFY DTCs 
  • Perform the DTC inspection for the following modules. (See DTC INSPECTION .)
    • PCM
    • TCM
    • Electronically controlled brake unit/DSC HU/CM
    • Dash-electrical supply unit
    • Body control module (BCM)
  • Are any DTCs displayed?
Yes Repair the malfunctioning location according to the applicable DTC troubleshooting.
(See DTC TABLE [PCM (PYUL)] .)
(See DTC TABLE [TCM (PM8AX-EC)] .)
(See DTC TABLE [DSC] .)
(See DTC TABLE [DASH_ESU] .)
(See DTC TABLE [BCM] .)
No Go to the next step.
3 VERIFY i-stop (ENGINE RESTART CONTROL) PERMIT CONDITION ITEMS 
WARNING:
  • To prevent an accident, work with two people when the vehicle is being driven (one person drives vehicle, other person operates M-MDS).
  • Observe legal speed limits when driving the vehicle and perform the procedure in a location where safety can be assured. 
  • Switch the ignition ON (engine off).
  • Display the PID related to the i-stop (engine restart control) permit conditions using the M-MDS. (See PID/DATA MONITOR INSPECTION .) (See PID/DATA MONITOR TABLE [PCM (PYUL)] .)
  • Drive the vehicle and perform engine stopping by i-stop.
  • Verify if the i-stop (engine restart control) permit conditions of the items which can be verified by the PID are met.
  • Are the permit conditions of all the items met?
Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification 1.
4 VERIFY VEHICLE CONDITIONS RELATED TO i-stop (ENGINE RESTART CONTROL) PERMIT CONDITIONS 
  • Drive the vehicle and perform engine stopping by i-stop.
  • Drive the vehicle and perform engine restart by i-stop.
    • Gear position: 2nd gear fixed mode
    • A/C set temperature: MAX or MIN
    • Windshield defroster switch: ON
  • Does the engine restart?
Yes Verify the i-stop (engine restart control) permit condition and perform the repair completion verification.
(See SYMPTOM TROUBLESHOOTING [PYUL] ).
No Go to the next step.
5 VERIFY AMBIENT TEMPERATURE SENSOR FOR MALFUNCTION  Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification 1.
(Refer to [AMBIENT TEMPERATURE SENSOR REMOVAL/INSTALLATION ] ).
6 VERIFY EVAPORATOR TEMPERATURE SENSOR FOR MALFUNCTION  Yes Full-auto air conditioner: 
  • Go to the next step.

Manual air conditioner: 
  • Go to Step 8.
No Repair or replace the malfunctioning location and perform the repair completion verification 1.
(Refer to [EVAPORATOR TEMPERATURE SENSOR REMOVAL/INSTALLATION ] ).
7 VERIFY PASSENGER COMPARTMENT TEMPERATURE SENSOR FOR MALFUNCTION  Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification 1.
(Refer to [PASSENGER COMPARTMENT TEMPERATURE SENSOR REMOVAL/INSTALLATION ] ).
8 DETERMINE IF MALFUNCTION CAUSED BY AIR MIX ACTUATOR MALFUNCTION  Yes Inspect the air mix door and linkage for sticking.
(Refer to [A/C UNIT DISASSEMBLY/ASSEMBLY ] ).
If there is no malfunction: 
  • Go to the next step.

If there is any malfunction: 
  • Repair or replace the malfunctioning location and perform the repair completion verification 1.
No Repair or replace the malfunctioning location and perform the repair completion verification 1.
(Refer to [AIR MIX ACTUATOR REMOVAL/INSTALLATION ] ).
9 VERIFY AIRFLOW MODE ACTUATOR FOR MALFUNCTION  Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification 1.
(Refer to [AIRFLOW MODE ACTUATOR REMOVAL/INSTALLATION ] ).
10 VERIFY EPS CONTROL MODULE FOR MALFUNCTION  Yes Implement the following procedure, then go to the next step.
  1. Switch the ignition off, and after 2 min or more have elapsed, switch the ignition ON.
  2. Start the engine and drive the vehicle on a straight road for 10 m {32 ft 10 in} or more at a speed of 10 km/h {6.2 mph} or more.
  3. Stop the vehicle with the wheels in the straight-ahead position.
No Repair or replace the malfunctioning location and perform the repair completion verification 1.
(Refer to [STEERING GEAR AND LINKAGE REMOVAL/INSTALLATION ] ).
Repair completion verification 1 VERIFY THAT VEHICLE IS REPAIRED 
  • Install/connect the part removed/disconnected during the troubleshooting procedure.
  • Has the malfunction symptom been eliminated?
Yes Complete the symptom troubleshooting. (Explain contents of repair to customer)
No Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error.
(See MALFUNCTION DIAGNOSIS FLOW [CONTROLLER AREA NETWORK (CAN)] .)
  • If the CAN communication is normal, perform the diagnosis from Step 1.