With Standard Transmission
ENGINE FAILS TO STARTConditions for Fault Tracing:
^ No DTCs present.
^ Starter motor operable.
^ Timing belt intact.
^ Fault is permanent.
FAULT SOURCES
MFI Fuel Pump
^ Open-circuit in supply lead, ground lead or signal lead to fuel pump relay.
^ Fuel pump relay signal lead short-circuited to ground or supply.
^ Open-circuit in supply lead or ground lead to fuel pump.
^ Open-circuit or contact resistance at fuel pump ground terminal.
^ Faulty fuel pump relay or fuel pump.
Engine Speed Sensor
^ Open-circuit in ICM signal ground.
^ Open-circuit in signal or ground lead.
^ Signal lead short-circuited to ground or supply.
^ Contact resistance at terminals.
^ Faulty sensor.
Camshaft Position Sensor
^ Signal lead short-circuited to ground or supply.
^ Supply lead short-circuited to ground.
^ Open-circuit in ground lead, ground terminal, signal lead or supply lead.
^ Faulty sensor.
Power Stage
^ Open-circuit in supply lead, ground lead or signal lead to power stage.
^ Power stage signal lead short-circuited to ground or supply.
^ Contact resistance in power stage connector.
^ Arcing in or faulty power stage/ignition coil, spark plug, ignition lead, distributor rotor or distributor cap.
Injectors
^ Open-circuit in MFI module power ground.
^ VSS signal lead to MFI module short-circuited to ground or supply.
^ Open-circuit in VSS signal lead to MFI module.
^ Open-circuit in injector signal or supply lead.
^ Injector signal lead short-circuited to ground or supply.
^ Faulty injector.
Mass Air Flow Sensor
^ Open-circuit in sensor supply lead, signal lead, power ground or signal ground.
^ Sensor signal lead short-circuited to ground or supply.
^ Contact resistance in sensor connector.
^ Faulty sensor.
Engine Coolant Temperature Sensor
^ Open-circuit in sensor ground or signal lead.
^ Sensor signal lead short-circuited to ground or supply.
^ Contact resistance in sensor connector.
^ Faulty sensor.
Fuel Pressure
^ Incorrect fuel pressure.
TESTING PROCEDURE
Volvo Scan Tool
^ Check that communication has been established between Scan Tool (ST) and both Control Modules.
MFI = LH 3.2 Engine Control Module
ICM = EZK 129 Ignition Control Module
If communication has been established:
- Check fuel pump.
If communication has not been established:
- See: OTHER ELECTRICAL FAULT TRACING / COMMUNICATION PROBLEMS WITH VOLVO SCAN TOOL.
Checking Fuel Pump
^ Switch OFF Ignition.
^ Remove fuse No. 1.
^ Switch ON Ignition.
^ Use fingers to lightly pinch hose connected to fuel pressure controller and reinstall fuse No. 1.
^ By feeling hose check that pump runs for a few seconds after fuse has been inserted.
Note: If pump does not run at first attempt, repeat test once or twice to verify that pump is not operating.
If pump runs:
- Proceed to: Checking Ignition Spark, section below.
If pump does not run:
- Proceed to: Starting Fuel Pump.
Starting Fuel Pump
^ Switch OFF Ignition.
^ Remove electrical distribution unit cover.
^ Remove fuel pump relay (position 103 in electrical distribution unit).
^ Switch ON Ignition.
^ Connect jumper lead across relay base terminals 1 and 3.
Fuel pump should start.
If pump starts:
- Proceed to: Checking Relay Ground Lead, section below.
If pump does not start:
- Proceed to: Checking Relay Supply.
Checking Relay Supply
^ Switch ON Ignition.
^ Remove fuel pump relay.
^ Connect voltmeter between relay base terminal 1 and ground.
Instrument should indicate battery voltage.
If reading is correct:
- Proceed to: Checking Fuel Pump Ground Lead.
If reading is incorrect:
- Check fuse No. 2 and replace as required.
If fuse is intact:
- Check lead between fuel pump relay terminal 1 and fuse No. 2 for open-circuit.
Checking Fuel Pump Ground Lead
^ Switch OFF Ignition.
^ Open fuel pump two-pin connector (C/BA) in luggage compartment.
^ Connect ohmmeter between fuel pump connector terminal 2 (female half, fuel pump relay side) and ground.
Instrument should indicate approx. 0 ohms.
If reading is approx. 0 ohms:
- Proceed to: Checking Fuel Pump.
If instrument indicates high resistance:
- Check pump ground terminal (31/48) for contact resistance and oxidation.
If instrument indicates infinite resistance:
- Check ground lead for open-circuit.
Checking Fuel Pump
^ Switch OFF Ignition.
^ Open fuel pump two-pin connector (C/BA).
^ Connect ohmmeter between fuel pump connector terminals 1 and 2 (male half, fuel pump side).
Instrument should indicate 0.5 - 2.0 ohms.
If reading is correct:
- Check lead between relay base terminal 3 and fuel pump for open-circuit.
If reading is incorrect:
- Try with new fuel pump.
Checking Relay Ground Lead
^ Switch OFF Ignition.
^ Remove fuel pump relay.
^ Connect ohmmeter between relay base terminal 2 and ground.
Instrument should indicate approx. 0 ohms.
If reading is correct:
- Proceed to: Checking signal lead voltage.
If reading is incorrect:
- Check lead between relay terminal 2 and ground terminal 31/51 for open-circuit.
Checking Signal Lead Voltage
^ Switch OFF Ignition.
^ Remove fuel pump relay.
^ Connect test box to MFI system and check ground terminals.
^ Plug MFI module into test box adapter.
^ Switch ON Ignition.
^ Connect voltmeter between #57 (MFI B27) and #20 (MFI A20) on test box.
Instrument should indicate approx. 0 Volts.
If reading is correct:
- Proceed to: Checking Resistance of Signal Lead to Ground.
If reading is incorrect:
- Check lead between MFI B27 and fuel pump relay terminal 4 for short-circuit to supply.
Checking Resistance of Signal Lead to Ground
^ Switch OFF Ignition.
^ Remove fuel pump relay.
^ Disconnect MFI module.
^ Connect ohmmeter between #57 (MFI B27) and #20 (MFI A20) on test box.
Instrument should indicate infinity.
If reading is correct:
- Proceed to: Checking Resistance of Signal Lead.
If reading is incorrect:
- Check lead between MFI B27 and fuel pump relay terminal 4 for short-circuit to ground.
Checking Resistance of Signal Lead
^ Switch OFF Ignition.
^ Remove fuel pump relay.
^ Connect ohmmeter between #57 (B27) on test box and fuel pump relay base terminal 4.
Instrument should indicate approx. 0 ohms.
If reading is correct:
- Proceed to: Checking Connector.
If reading is incorrect:
- Check lead between MFI B27 and fuel pump relay terminal 4 for open-circuit.
Checking Connector
^ Switch OFF Ignition.
^ Reinstall fuel pump relay.
^ Try to start engine.
If engine starts:
- Fault is due to poor connection in pump relay base.
- Check relay base and relay for contact resistance and oxidation.
If engine does not start:
- Try with new fuel pump relay.
Checking Ignition Spark
^ Switch OFF Ignition.
^ Disconnect one plug cap.
^ Insert new spark plug in cap.
^ Ground plug against engine.
^ Operate starter motor and check whether plug sparks.
If spark is present:
- Proceed to: Checking Spark Plugs.
If spark is not present:
- Proceed to: Checking RPM Sensor Signal to Ignition Control Module, section below.
Checking Spark Plugs
^ Switch OFF Ignition.
^ Remove one plug from engine and insert in plug cap.
^ Install new plug in place of plug removed.
^ Ground loose plug against engine.
^ Operate starter motor and check if plug sparks.
If spark is present:
- Proceed to: Checking MAF Sensor Signal, section below.
If spark is not present:
- Replace all plugs.
Checking RPM Sensor Signal to Ignition Control Module
^ Switch ON Ignition.
^ Operate starter motor.
Engine should turn at between 100 and 300 rpm.
If speed is correct:
- Proceed to: Checking Power Stage Supply Lead, section below.
If speed is incorrect:
- Proceed to: Checking RPM Sensor Signal.
Checking RPM Sensor Signal
^ Connect test box to DI system and check ground terminals.
^ Plug Ignition Control Module (ICM) into test box connector.
^ Connect voltmeter across #1 (ICM A1) and #2 (ICM A2) on test box.
^ Operate starter motor.
Instrument should indicate 300 - 400 mV (a.c.).
If reading is correct:
- Carry out fault tracing of Camshaft Position Sensor. See TESTING BY TROUBLE CODE / IGNITION SYSTEM / DTC 3-1-4 CAMSHAFT POSITION SENSOR SIGNAL MISSING.
If reading is incorrect:
- Carry out fault tracing of Engine Speed Sensor Signal. See: TESTING BY TROUBLE CODE / IGNITION SYSTEM / DTC 1-3-1 Engine SPEED SENSOR SIGNAL.
Checking Power Stage Supply Lead
^ Switch ON Ignition.
^ Disconnect power stage.
^ Connect voltmeter between power stage connector terminal 3 and ground.
Instrument should indicate battery voltage.
If reading is correct:
- Proceed to: Checking Power Stage Ground Lead.
If reading is incorrect:
- Check fuse No. 4 and replace as required.
If fuse is intact:
- Check lead between power stage connector terminal 3 and fuse No. 4 for open-circuit.
Checking Power Stage Ground Lead
^ Switch OFF Ignition.
^ Disconnect power stage.
^ Connect ohmmeter between power stage connector terminal 1 and ground.
Instrument should indicate approx. 0 ohms.
If reading is correct:
- Proceed to: Checking Trigger Signal.
If reading is incorrect:
- Check lead between power stage connector terminal 1 and ground for open-circuit.
Checking Trigger Signal
^ Switch ON Ignition.
^ Disconnect power stage.
^ Connect voltmeter between power stage connector terminal 4 and ground.
^ Run starter motor.
Instrument should indicate approx. 1.5 Volts (a.c.).
If reading is correct:
- Proceed to: Checking for Spark From Ignition Coil, section below.
If instrument indicates approx. 0 Volts:
- Proceed to: Checking Signal Lead.
If instrument indicates over 5 Volts:
- Check lead between ICM B13 and power stage connector terminal 4 for short-circuit to supply.
Checking signal lead
^ Switch OFF Ignition.
^ Disconnect power stage.
^ Connect ohmmeter between #43 (ICM B13) on test box and power stage connector terminal 4.
Instrument should indicate approx. 0 ohms.
If reading is correct:
- Check lead between ICM B13 and power stage connector terminal 4 for short-circuit to ground.
If reading is incorrect:
- Check lead between ICM B13 and power stage connector terminal 4 for open-circuit.
Checking for Spark From Ignition Coil
^ Switch ON Ignition.
^ Disconnect power stage.
^ Disconnect high-tension lead (king lead) from distributor cap.
^ Hold lead 3 - 5 mm from ground point.
^ Operate starter motor and check for spark.
If spark is present:
- Proceed to: Checking Distributor Rotor and Cap.
If spark is not present:
- Try with new ignition coil/power stage.
Checking Distributor Rotor and Cap
^ Reinstall spark plug which has been removed and reconnect plug cap.
^ Reconnect ignition coil king lead to distributor cap.
^ Try to start engine.
If engine starts:
- Fault is due to poor connection in power stage connector.
- Check connector for contact resistance and oxidation.
If engine does not start:
- Check distributor cap, distributor rotor and ignition leads for damage, moisture or dirt. Replace leads as required.
Checking MAF Sensor Signal
^ Connect test box to MFI module and check ground terminals.
^ Plug MFI module into test box adapter.
^ Switch ON Ignition.
^ Connect voltmeter across #13 (MFI A13) and #20 (MFI A20) on test box.
Instrument should indicate approx. 2.8 Volts.
If reading is correct:
- Proceed to: Checking Injectors, section below.
If reading is incorrect:
- Proceed to: Checking Supply to MAF Sensor.
Checking Supply to MAF Sensor
^ Switch ON Ignition.
^ Disconnect sensor.
^ Connect voltmeter between sensor connector terminal 3 and ground.
Instrument should indicate battery voltage.
If reading is correct:
- Proceed to: Checking MAF Sensor Signal Ground.
If reading is incorrect:
- Check lead between sensor connector terminal 3 and battery positive terminal for open-circuit.
Checking MAF Sensor Signal Ground
^ Switch OFF Ignition.
^ Disconnect sensor.
^ Connect ohmmeter between sensor connector terminal 1 and ground.
Instrument should indicate 500 - 1500 ohms.
If reading is correct:
- Proceed to: Checking MAF Sensor Power Ground.
If reading is incorrect:
- Check lead between ICM module A12 and sensor connector terminal 1 for open-circuit.
Checking MAF Sensor Power Ground
^ Switch OFF Ignition.
^ Disconnect sensor.
^ Connect ohmmeter between sensor connector terminal 2 and ground.
Instrument should indicate approx. 0 ohms.
If reading is correct:
- Proceed to: Checking MAF Sensor Connector.
If reading is incorrect:
- Check lead between MFI A8 and sensor connector terminal 2 for open-circuit.
Checking MAF Sensor Connector
^ Switch ON Ignition.
^ Disconnect sensor.
^ Connect voltmeter across #13 (MFI A13) and #20 (MFI A20) on test box.
Instrument should indicate approx. 2.8 Volts.
If reading is correct:
- Fault is due to poor connection in sensor connector.
- Check connector for contact resistance and oxidation.
If instrument indicates approx. 0 Volts:
- Proceed to: Checking Resistance of MAF Sensor Signal Lead.
If instrument indicates battery voltage:
- Proceed to: Checking Voltage in MAF Sensor Signal Lead, section below.
Checking Resistance of MAF Sensor Signal Lead
^ Switch OFF Ignition.
^ Disconnect sensor.
^ Connect ohmmeter between sensor connector terminal 4 and ground.
Instrument should indicate approx. 25K ohms.
If reading is correct:
- Try with new sensor.
If instrument indicates approx. 0 ohms:
- Check lead between MFI terminal A13 and sensor connector terminal 4 for short-circuit to ground.
If instrument indicates infinity:
- Check lead between MFI terminal A13 and sensor connector terminal 4 for open-circuit.
Checking Voltage in MAF Sensor Signal Lead
^ Switch ON Ignition.
^ Disconnect sensor.
^ Connect voltmeter between sensor connector terminal 4 and ground.
Instrument should indicate approx. 0 Volts.
If reading is correct:
- Try with new sensor.
If reading is incorrect:
- Check lead between MFI terminal A13 and sensor connector terminal 4 for short-circuit to supply.
Checking Injectors
^ Switch OFF Ignition.
^ Disconnect one injector connector. Connect voltmeter across injector connector terminals 1 and 2.
^ Operate starter motor.
Instrument should indicate 100 - 700 mV depending on engine temperature.
If reading is correct:
- Proceed to: Checking ECT Sensor Signal, section below.
If reading is incorrect:
- Proceed to: Checking RPM Sensor Signal to MFI System.
Checking RPM sensor signal to MFI System
^ Switch OFF Ignition.
^ Connect voltmeter across #51 (MFI B21) and #20 (MFI A20) on test box.
^ Run starter motor.
Instrument should indicate 4 - 7 Volts.
If reading is correct:
- Proceed to: Checking Injector Supply, section below.
If instrument indicates approx. 0 Volts:
- Proceed to: Checking RPM Sensor Signal Lead.
If instrument indicates battery voltage:
- Check lead between ICM B21 and MFI B21 for short-circuit to supply.
Checking RPM Sensor Signal Lead
^ Switch OFF Ignition.
^ Connect ohmmeter between #51 (MFI B21) and #20 (MFI A20) on test box.
^ Wait approx. one minute.
If reading is approx. 0 ohms:
- Check lead between ICM B21 and MFI terminal B21 for short-circuit to ground.
If resistance is infinite:
- Check lead between ICM B21 and MFI terminal B21 for open-circuit.
Checking Injector Supply
^ Switch ON Ignition.
^ Disconnect one injector
^ Connect voltmeter between terminal 1 of disconnected connector and ground.
^ Operate starter motor.
Instrument should indicate 9 - 12 Volts.
If reading is correct:
- Proceed to: Checking Injector Signal Lead.
If reading is incorrect:
- Check lead between injector connector terminal 1 and main relay (2/32) terminal 3 for open-circuit.
Checking Injector Signal Lead
^ Switch ON Ignition.
^ Disconnect all injectors.
^ Connect voltmeter between terminal 2 of any injector connector and ground.
Instrument should indicate approx. 0 Volts when voltage has stabilized.
If reading is correct:
- Proceed to: Checking Resistance of Signal Lead.
If reading is incorrect:
- Check lead between MFI terminal A9 and injector connector terminal 2 for short-circuit to supply.
Checking Resistance of Signal Lead
^ Switch OFF Ignition.
^ Disconnect injectors.
^ Connect ohmmeter between #9 (MFI A9) on test box and terminal 2 of any injector connector.
Instrument should indicate approx. 0 ohms.
If reading is correct:
- Proceed to: Checking Injector Resistance.
If reading is incorrect:
- Check lead between MFI terminal A9 and injector connector terminal 2 for open-circuit.
Checking Injector Resistance
^ Switch OFF Ignition.
^ Disconnect injectors.
^ Connect ohmmeter between terminals 1 and 2 of each injector connector.
Instrument should indicate approx. 16 ohms.
If all readings are correct:
- Check lead between MFI terminal A9 and injector connector terminal 2 for short-circuit to ground.
If all readings are not correct:
- Replace faulty injector as needed.
Checking ECT Sensor Signal
^ Switch OFF Ignition.
^ Connect ohmmeter between #14 (MFI A14) and #15 (MFI A15) on test box.
Instrument should indicate approx. 2200 ohms at 25°C (77°F) (see chart).
If reading is correct:
- Proceed to: Checking Fuel Pressure, section below.
If reading is incorrect:
- Proceed to: Checking ECT Sensor Ground Lead.
Checking ECT Sensor Ground Lead
^ Switch OFF Ignition.
^ Disconnect engine cooling fan.
NOTE: If engine cooling fan runs, wait until fan cuts out.
^ Disconnect ECT sensor.
^ Connect ohmmeter between sensor connector terminal 1 (ICM side) and ground.
Instrument should indicate approx. 0 ohms.
If reading is correct:
- Proceed to: Checking ECT Sensor Signal Lead.
If reading is incorrect:
- Check lead between MFI terminal A14 and sensor connector terminal 1 for open-circuit.
Checking ECT Sensor Signal Lead
^ Switch ON Ignition.
^ Disconnect sensor.
^ Connect voltmeter between sensor connector terminal 2 (control module side) and ground.
Instrument should indicate approx. 5 Volts.
If reading is correct:
- Proceed to: Checking ECT Sensor, section below.
If instrument indicates approx. 0 Volts:
- Proceed to: Checking Resistance of ECT Sensor Signal Lead.
If Instrument indicates battery voltage:
- Check lead between MFI terminal A15 and sensor connector terminal 2 for short-circuit to supply.
If fault has been corrected:
- Measure sensor resistance.
Resistance should be approx. 2200 ohms at 25°C (77°F) (see chart).
If sensor resistance is not correct:
- Try with new sensor.
Checking Resistance of ECT Sensor Signal Lead
^ Switch OFF Ignition.
^ Disconnect sensor.
^ Connect ohmmeter between #15 (MFI A15) on test box and sensor connector terminal 2.
If instrument indicates approx. 0 ohms:
- Check lead between MFI A15 and sensor connector terminal 2 for short-circuit to ground.
If instrument indicates infinity:
- Check lead between MFI A15 and sensor connector terminal 2 for open-circuit.
Checking ECT Sensor
^ Switch OFF Ignition.
^ Reconnect sensor.
^ Connect ohmmeter between #14 (MFI A14) and #15 (MFI A15) on test box.
Instrument should indicate approx. 2200 ohms at 25°C (77°F) (see chart).
If reading is correct:
- Fault is due to poor connection in sensor connector.
- Check connector for contact resistance and oxidation.
If reading is incorrect:
- Try with new sensor.
Checking Fuel Pressure
^ Switch OFF Ignition.
^ Check fuel pressure and residual pressure.
- See: FUEL DELIVERY AND AIR INDUCTION / FUEL PRESSURE.
If fuel pressure and residual pressure are correct:
- Check all signals to and from MFI module and ICM.
If fuel pressure and residual pressure are incorrect:
- Carry out repairs as required.