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    Search for cross reference part numbers for other manufacturers of the parts you're looking for.

    Cross Reference information is provided as a guide only. Please refer to the "Applications" lookup tabs for more detail. Materials and designs will differ among brands, so plugs are not exactly alike. Always check with your OE service manual for proper installation and settings.

    System Diagnosis

    Proper vehicle diagnosis requires a plan before you start

    Following a set procedure to base your troubleshooting on will help you find the root cause of a problem and prevent unnecessary repeat repairs .

    STEP ONE: Understand the Customer’s Concern

    • Information collection beyond the basics.
    • Questions asked MUST be related To the system you will be working on and the customer complaint

    STEP TWO: Check for Technical Service Bulletins

    • Every vehicle that comes into the shop for a repair (not necessary for routine maintenance) should be checked for TSBs, This can save you hours of troubleshooting.

    STEP THREE: Conduct a Systematic Diagnosis

    • This step will be different for every system
    • Follow the troubleshooting steps for the system you are working on.
    • Make sure to check EVERY component of the system and that they are in proper working order.
    • Document your diagnosis including tests and results

    STEP FOUR: Complete and Confirm the Repair

    • Make sure you have taken care of the customer’s concerns.
    • Try to duplicate the conditions that were present when the vehicle failed

    Starting System Troubleshooting Chart

    Symptom Possible Cause Corrective Action
    Engine will not crank Dead battery Check battery state of charge. Recharge if possible. Replace if necessary/td>
    Melted fusible link Replace fusible link
    Loose connections Clean and tighten connections
    Key switch or start switch contacts in poor condition Replace switch as necessary
    Solenoid hold-in coil open. Pull-in coil open or shorted. Replace starter
    Solenoid contacts worn away Replace starter
    Mechanical problem in engine Check engine
    Engine cranks too slowly to start Weak battery Check battery. Recharge if possible. Replace if necessary
    Loose or corroded connections Clean and tighten connections
    Faulty starter Test starter, Replace if necessary
    Starter spins, but engine will not crank Faulty over-running clutch Check over-running clutch, replace starter if necessary
    Damaged or worn starter pinion gear or engine ring gear. Check gears for damage or wear. Replace starter or ring gear

    Starting System inspection checklist

    Begin with a thorough visual inspection of system and components

    System tests:

    Battery

    • Load test
    • Confirm charging system operation

    System cables & wires

    • Make sure all connections are clean and tight
    • Check wires for fraying, insulation damage, and other physical damage

    Voltage drop test

    • Check voltage drop on the complete circuit
    • If a problem is detected check the positive side and negative side separately to isolate problem

    Check voltage at “KS” terminal on the starter with the ignition switch in the start position

    • Typically 11.4-volt minimum (check vehicle service manual for correct specification)

    System voltage drop test

    The diagram shows a carbon pile tester. Test can be done with electronic system tester, follow instructions included with the tool.

    Subtract (-) VM B from VM A. Loss not to exceed 0.5V.

    Proceed to positive & negative cable. Voltage loss tests if total loss exceeds specs.

    Positive side voltage drop test

    Test can be performed with:

    • Electronic tester
    • Carbon pile load tester
    • Cranking engine (If cranking engine)
      1. Disable the fuel or ignition system to keep the engine from starting during the test
      2. DO NOT crank the engine for longer than 10 seconds at a time
      3. Wait a minimum of 60 seconds before cranking engine again to cool the starter

    Ground side voltage drop test

    Test can be performed with:

    • Electronic tester
    • Carbon pile load tester
    • Cranking engine (If cranking engine)
      1. Disable the fuel or ignition system to keep the engine from starting during the test
      2. DO NOT crank the engine for longer than 10 seconds at a time
      3. Wait a minimum of 60 seconds before cranking engine again to cool the starter