Engine Fails to Start
FAULT TRACING INFORMATIONConditions
^ DTCs absent.
^ Starter motor functioning.
^ Camshaft belt OK.
^ Fault permanent.
FAULT SOURCES
Fuel Pump:
^ Break in signal or power lead to Fuel Pump (FP) Relay.
^ FP relay signal lead short circuited to ground or live.
^ Break in ground or power lead to Fuel Pump.
^ Contact resistance in connections.
^ Defective Fuel Pump relay or Fuel Pump.
Engine Speed Sensor:
^ Break in ground or signal lead.
^ Signal lead short circuited to ground or live.
^ Contact resistance in connections.
^ Defective Engine Speed (RPM) Sensor.
Ignition Components:
^ Break in power lead to Ignition coils.
^ Contact resistance in connections and control points.
^ Defective Ignition relay.
^ Defective spark plug.
^ Break in ground, signal or power lead to Ignition relay.
Mass Air Flow Sensor:
^ Break in power ground, signal ground, signal or power lead.
^ Signal lead short circuited to ground or live.
^ Damaged or loose intake hoses between Mass Air Flow (MAF) Sensor and Throttle Body.
^ Contact resistance in connections.
^ Defective MAF sensor.
Engine Coolant Temperature Sensor:
^ Break in ground or signal lead.
^ Signal lead short circuited to ground or live.
^ Contact resistance in connections.
^ Defective Engine Coolant Temperature (ECT) Sensor.
Fuel Pressure:
^ Faulty fuel pressure.
TESTING PROCEDURE
Scan Tool
^ Check that the Scan Tool (ST) is in contact with ECM.
If ST is in contact with ECM:
- Proceed to: Fuel Pump, section below.
If ST not in contact with ECM:
- Communication problems with Scan Tool.
Fuel Pump
^ Switch Ignition OFF.
^ Remove fuse No 1 (11B/1) in central relay unit.
^ Switch ignition ON.
^ Grip fuel hose which is connected to fuel pressure regulator lightly with fingers and replace fuse.
^ Check that FP runs for a few seconds after fuse has been replaced. When FP is running a pulse can be felt with the fingers.
NOTE: If pump does not on at first attempt, repeat test a few times to confirm pump is not running.
If FP runs:
- Proceed to: Check Spark, section below.
If FP does not run:
- Proceed to: Start Fuel Pump.
Start Fuel Pump
^ Switch Ignition OFF.
^ Remove fuse No 1 (11B/1) in central relay unit.
^ Remove FP relay in fuse box on left side of Instrument panel position 2.
^ Connect a lead between contact 1 and 3 on relay base.
^ Switch Ignition ON.
^ Grip hose connected fuel pressure regulator lightly with fingers and replace fuse.
^ Check that FP runs for a few seconds after fuse has been replaced. When FP Is running, pulses can be felt with the fingers.
If FP runs:
- Proceed to: Check Fuel Pump Relay Signal Lead, section below.
If FP does not run:
- Check voltage to relay.
Check Voltage to Relay
^ Ignition OFF.
^ Remove FP relay.
^ Ignition ON.
^ Connect a voltmeter between relay base contact 1 and ground.
Voltmeter should read battery voltage.
If value OK:
- Check FP ground lead.
If value differs:
- Check fuse No 4 (11B/4) in central relay unit. Replace fuse as necessary.
If fuses OK:
- Check lead between FP relay contact 1 and fuse 4 for break.
Check Fuel Pump Ground Lead
^ Ignition OFF.
^ Disconnect FP 4-pin connector in trunk.
^ Connect an ohmmeter between FP connector contact 4 (to FP relay) and ground.
Ohmmeter should read approx. 0 ohms.
If value OK:
- Proceed to: Check Fuel Pump, section below.
If value differs:
- Check fuel pump control point.
Check Fuel Pump Control Point
^ Ignition OFF.
^ FP disconnected.
^ Check FP control point (31/6) at left seat control mechanism for contact resistance and oxidation.
^ Connect an ohmmeter between FP connector contact 4 (to FP relay) and ground.
Ohmmeter should read approx. 0 ohms.
If value OK:
- Source of fault is bad contact in FP control point.
If value differs:
- Check lead between FP connector contact 4 and control point (31/6) at left seat control mechanism for break.
Check Fuel Pump
^ Ignition OFF.
^ FP disconnected.
^ Connect an ohmmeter between FP connector contact 1 and 4 (to FP).
Ohmmeter should read approx. 0.5 - 2 ohms.
If value OK:
- Check lead between FP relay contact 3 and FP contact 1 for break.
If value differs:
- Test with a new FP.
Check Fuel Pump Relay Signal Lead
^ Ignition ON.
^ Remove FP relay.
^ Connect a voltmeter between relay base contact 4 and ground.
Voltmeter should read approx. 0 Volts.
If value OK:
- Check signal lead resistance to ground.
If value differs:
- Check lead between FP relay contact 4 and ECM #3 for short circuit to live.
Check Signal Lead Resistance To Ground
^ Ignition OFF.
^ FP relay removed.
^ Connect an ohmmeter between relay base contact 4 and ground.
Ohmmeter should read infinite resistance.
If value OK:
- Check signal lead resistance.
If value differs:
- Check lead between FP relay contact 4 and ECM #3 for short circuit to ground.
Check Signal Lead Resistance
^ Ignition OFF.
^ FP relay removed.
^ Connect breakout box and check control points.
^ ECM disconnected.
^ Connect an ohmmeter between relay base contact 4 and #3 on breakout box.
Ohmmeter should read approx. 0 ohms.
If value OK:
- Proceed to: Check Connector, section below.
If value differs:
- Check lead between FP relay contact 4 and ECM #3 for break.
Check Connector
^ Ignition OFF.
^ Replace FP relay.
^ Connect ECM and FP.
^ Test engine starts.
If engine starts:
- Source of fault is bad contact in ECM, FP relay or FP connector. Check connectors for contact resistance and oxidation.
If engine does not start:
- Test with new FP relay.
Check Spark
^ Ignition OFF.
^ Disconnect an ignition coil.
^ Mount a new spark plug in the Ignition coil.
^ Place spark plug against engine.
^ Turn with starter motor and check if spark at spark plug.
If there is spark:
- Proceed to: Check Spark Plug, section below.
If there is no spark:
- Check RPM sensor signal.
Check RPM Sensor Signal
^ Ignition ON.
^ Turn with starter motor.
^ Read off engine speed.
Engine speed should read 150 rpm when engine turned on starter motor.
If speed OK:
- Check voltage from ignition relay.
If speed is 0 rpm:
- Fault trace RPM sensor.
- See: TESTING BY TROUBLE CODE / DTC 1-3-1 RPM SENSOR SIGNAL. PERMANENT FAULT, SIGNAL ABSENT.
Check Voltage From Ignition Relay
^ Ignition ON.
^ Connect a voltmeter between test socket to cylinder 1 at rear of engine and ground.
Voltmeter should read battery voltage.
If value OK:
- Proceed to: Check Signal From Mass Air Flow Sensor, section below.
If value differs:
- Check ignition relay ground lead.
Check Ignition Relay Ground Lead
^ Ignition OFF.
^ Disconnect ignition relay in central relay unit position J.
^ Connect an ohmmeter between relay base contact 4 and ground.
Ohmmeter should read approx. 0 ohms.
If value OK:
- Proceed to: Check Voltage to Ignition Relay, section below.
If value differs:
- Check ignition relay control point.
Check Ignition Relay Control Point
^ Ignition OFF.
^ Ignition relay disconnected.
^ Check Ignition Relay Control point (34/42) for contact resistance and oxidation.
^ Connect an ohmmeter between relay base contact 4 and ground.
Ohmmeter should read approx. 0 ohms.
If value OK:
- Source of fault is bad contact in ignition relay control point.
If value differs:
- Check lead between ignition relay contact 4 and junction box 34/42 in central relay unit for break.
Check Voltage to Ignition Relay
^ Ignition ON.
^ Ignition relay disconnected.
^ Connect a voltmeter between relay base contacts 1 and 4.
Voltmeter should read battery voltage.
If value OK:
- Proceed to: Check Signal Lead to Ignition Relay, section below.
If value differs:
- Check fuse 7 (11B/7) in central relay unit.
If fuse OK:
- Check signal from main relay.
If fuse is not OK:
- Check leads between:
^ fuse 7 and ignition relay contact 1.
^ HO2S and ignition relay contact 5.
^ ignition coils and ignition relay contact 3 for short circuit to ground.
Check Signal From Main Relay
^ Ignition ON.
^ Connect a voltmeter between upper socket in fuse-holder for fuse 7 (11B/7) in central relay unit and ground.
Voltmeter should read battery voltage.
If value OK:
- Check lead between fuse 7 and ignition relay in central relay unit position J contact 1 for break.
If value differs:
- Check lead between fuse 7 and main relay in central relay unit position C contact 3 for break.
Check Signal Lead to Ignition Relay
^ Ignition ON.
^ Ignition relay disconnected.
^ Connect a voltmeter between relay base contact 2 and ground.
Voltmeter should read battery voltage.
If value OK:
- Test with a new ignition relay.
If value differs:
- Check lead between Ignition relay contact 2 and FP relay in fuse box at left side of instrument panel, position 2, contact 5 for break.
Check Spark Plug
^ Ignition OFF.
^ Replace all spark plugs.
NOTE: It is very important that the correct spark plugs are used. Also check gaps of new plugs before fitting. Spark plug gap should be 0.7 - 0.8 mm.
^ Connect Ignition lead to spark plug.
^ Test START engine.
If engine starts:
- Source of fault is bad spark plugs.
If engine does not start:
- Check signal from Mass Air Flow (MAF) Sensor.
Check Signal From Mass Air Flow Sensor
^ Ignition ON.
^ Turn with starter motor.
^ Read off load signal.
Value should read approx. 2.3 - 2.4 Volts.
If value OK:
- Check Engine Coolant Temperature (ECT) Sensor signal.
If value under 2.2 Volts:
- Fault trace MAF sensor.
- See: TESTING BY TROUBLE CODE / DTC 1-2-1 MAF SENSOR SIGNAL, PERMANENT FAULT, SIGNAL TOO LOW.
If value above 2.5 Volts:
- Fault trace MAF sensor.
- See: TESTING BY TROUBLE CODE / DTC 1-2-1 MAF SENSOR SIGNAL, PERMANENT FAULT, SIGNAL TOO HIGH.
Check Engine Coolant Temperature Sensor Signal
^ Ignition ON.
^ Connect multimeter P/N 9996525 to temperature box P/N 9995281 and temperature sensor P/N 9995282.
WARNING: RISK OF SCALDING.
^ Clamp hose between cooler and thermostat housing with hose pliers, carefully bend downwards and slack off from thermostat housing.
^ Insert sensor into thermostat housing and replace hose. It Is important that the sensor is near the thermostat.
^ Read off temperature on multimeter.
^ Check that the Scan Tool (ST) reads correct engine temperatures. After checking, replace hose and expansion tank cover.
Value can vary 5 - 10°C (10 - 20°F) because ECT sensor is mounted at rear of engine.
If ST reads correct engine temperature:
- Check fuel and residual pressure.
If ST reads too low engine temperature:
- Fault trace ECT sensor.
- See: TESTING BY TROUBLE CODE / DTC 1-2-3 ECT SENSOR SIGNAL, PERMANENT FAULT, SIGNAL TOO HIGH.
If ST reads too high engine temperature:
- Fault trace ECT sensor.
- See: TESTING BY TROUBLE CODE / DTC 1-2-3 ECT SENSOR SIGNAL, PERMANENT FAULT, SIGNAL TOO LOW.
Check Fuel and Residual Pressure
^ Ignition OFF.
^ Check fuel and residual pressure.
If fuel and residual pressure OK:
- Connect breakout box.
If fuel and residual pressure not OK:
- Fix as necessary.
Connect Breakout Box
^ Connect breakout box and check all control points.
^ Connect ECM.
^ Check all signals to and from ECM.