What can cause a Volvo XC60 to have intermittent starting issues?

Intermittent Starting Issues in Volvo XC60 (2008-2017)

Intermittent starting issues in a Volvo XC60 can be caused by several factors. Below are the common symptoms, diagnostic steps, required tools, and repair instructions.

Step 1: Visual Inspection

• Tools Required: Flashlight
• Instructions:
  • Inspect the battery terminals for corrosion or looseness.
  • Check the wiring harness for any signs of wear or damage.
  • Look for any blown fuses related to the ignition system.

Step 2: Battery Test

• Tools Required: Digital Multimeter, Battery Tester
• Instructions:
  • Measure the voltage across the battery terminals using a multimeter. A healthy battery should read around 12.6 volts when the vehicle is off.
  • If voltage is below 12.4 volts, charge the battery and retest.
  • Use a battery tester to check for a load test. Replace if the battery fails.

Step 3: Starter Relay and Fuse Check

• Tools Required: Fuse Puller, Multimeter
• Instructions:
  • Locate the starter relay in the engine compartment fuse box.
  • Check the fuse associated with the starter system for continuity using a multimeter.
  • If the fuse is blown, replace it and test the starter relay by swapping it with another relay of the same type.

Step 4: Ignition Switch Test

• Tools Required: Multimeter
• Instructions:
  • Test the ignition switch for continuity when in the 'Start' position. Disconnect the ignition switch connector and use a multimeter to check for continuity between the terminals.
  • If there is no continuity when the key is turned, replace the ignition switch.

Step 5: Starter Motor Functionality

• Tools Required: Multimeter, Jump Leads
• Instructions:
  • With the vehicle in neutral and the parking brake engaged, use jump leads to apply direct power to the starter motor from the battery.
  • If the starter engages and the engine cranks, the starter is likely good. If it does not crank, the starter motor may need to be replaced.

Step 6: Scan for Diagnostic Trouble Codes (DTCs)

• Tools Required: OBD-II Scanner
• Instructions:
  • Connect the OBD-II scanner to the vehicle's diagnostic port.
  • Read and record any fault codes related to the starting system, such as P0685 (ECM Power Relay Control Circuit).

Step 7: Fuel System Check

• Tools Required: Fuel Pressure Gauge
• Instructions:
  • Connect a fuel pressure gauge to the Schrader valve on the fuel rail.
  • Turn the ignition to the 'On' position (without starting the engine) and observe the pressure. It should be within the manufacturer’s specified range (usually around 50-60 psi).
  • If pressure is low, check the fuel pump operation and fuel filter condition.

Repair Instructions

Replacing a Faulty Battery

1. Disconnect the negative (-) terminal first, followed by the positive (+) terminal.
2. Remove the battery hold-down bracket.
3. Lift the battery out and replace it with a new one.
4. Reinstall the hold-down bracket and connect the positive (+) terminal first, then the negative (-) terminal.

Replacing the Starter Motor

1. Disconnect the negative battery terminal.
2. Raise the vehicle and safely support it on jack stands.
3. Remove the electrical connections from the starter (usually two: a main power cable and a smaller trigger wire).
4. Unbolt the starter motor from the transmission bell housing (typically 2-3 bolts).
5. Remove the starter motor and install the new one. Reverse the process to reinstall.

Replacing the Ignition Switch

1. Disconnect the battery.
2. Remove the steering column covers to access the ignition switch.
3. Disconnect the wiring harness from the ignition switch.
4. Remove the screws holding the ignition switch in place.
5. Install the new ignition switch and reassemble the steering column.

Replacing the Fuel Pump

1. Relieve fuel system pressure.
2. Disconnect the battery.
3. Access the fuel pump (may require removal of the rear seat or fuel tank).
4. Disconnect the fuel lines and electrical connector from the pump.
5. Remove the pump assembly and replace it with a new one. Reassemble in reverse order.

Conclusion

Intermittent starting issues in the Volvo XC60 can stem from multiple sources including battery, ignition switch, starter motor, or fuel system failures. By following the above diagnostic steps and repair instructions, you can identify the root cause and resolve the issue effectively. Always consult the vehicle's service manual for specific torque specifications and procedures.