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Feed Circuit Test

WARNING: This page is about a different car, the 2012 Chrysler 300. However, it is still accessible from the selected car via links, so may be relevant.

The starter feed circuit test (voltage drop method) will determine if there is excessive resistance in high-amperage feed circuit. For complete starter wiring circuit diagrams, refer to Wiring Diagrams.

When performing these tests, it is important to remember that voltage drop is giving an indication of resistance between two points at which voltmeter probes are attached.

Example:  When testing resistance of positive battery cable, touch voltmeter leads to positive battery cable clamp and cable connector at starter solenoid. If you probe positive battery terminal post and cable connector at starter solenoid, you are reading combined voltage drop in positive battery cable clamp-to-terminal post connection and positive battery cable.

The following operation will require a voltmeter accurate to 1/10 (0.10) volt. Before performing tests, be certain that following procedures are accomplished:

Fig 1: Testing Battery Negative Connection Resistance - Typical
GC0080026Courtesy of CHRYSLER GROUP, LLC
1 - VOLTMETER
2 - BATTERY
  1. Connect positive lead of voltmeter (1) to negative battery cable terminal post. Connect negative lead of voltmeter to negative battery cable clamp. Refer to Fig 1. Press and hold the ignition in Start  position. Observe voltmeter. If voltage is detected, correct poor contact between cable clamp and terminal post. Note: Certain diesel equipped models use dual batteries. If equipped with dual battery system, procedure must be performed twice, once for each battery. 
    Fig 2: Testing Battery Positive Connection Resistance - Typical
    GC0080027Courtesy of CHRYSLER GROUP, LLC
    1 - VOLTMETER
    2 - BATTERY
  2. Connect positive lead of voltmeter to positive battery terminal post. Connect negative lead of voltmeter to battery positive cable clamp. Refer to Fig 2. Press and hold the ignition in Start  position. Observe voltmeter. If voltage is detected, correct poor contact between cable clamp and terminal post. Note: Certain diesel equipped models use dual batteries. If equipped with dual battery system, this procedure must be performed twice, once for each battery. 
    Fig 3: Testing Battery Positive Cable Resistance - Typical
    GC0080028Courtesy of CHRYSLER GROUP, LLC
    1 - BATTERY
    2 - VOLTMETER
    3 - STARTER MOTOR
  3. Connect voltmeter to measure between battery positive terminal post and starter solenoid battery terminal stud. Refer to Fig 3. Press and hold the ignition in Start  position. Observe voltmeter. If reading is above 0.2 volt, clean and tighten battery cable connection at solenoid. Repeat test. If reading is still above 0.2 volt, replace faulty positive battery cable. Note: Certain diesel equipped models use dual batteries. If equipped with dual battery system, this procedure must be performed on driver side battery only. 
    Fig 4: Testing Ground Circuit Resistance - Typical
    GC0080029Courtesy of CHRYSLER GROUP, LLC
    1 - VOLTMETER
    2 - BATTERY
    3 - ENGINE GROUND
  4. Connect voltmeter to measure between negative battery terminal post and a good clean ground on engine block. Refer to Fig 4. Press and hold the ignition in Start  position. Observe voltmeter. If reading is above 0.2 volt, clean and tighten negative battery cable attachment on engine block. Repeat test. If reading is still above 0.2 volt, replace faulty negative battery cable. Note: Certain diesel equipped models use dual batteries. If equipped with dual battery system, this procedure must be performed twice, once for each battery. 
    Fig 5: Testing Starter Ground - Typical
    GC0080030Courtesy of CHRYSLER GROUP, LLC
    1 - STARTER MOTOR
    2 - BATTERY
    3 - VOLTMETER
  5. Connect positive lead of voltmeter to starter housing. Connect negative lead of voltmeter to negative battery terminal post. Refer to Fig 5. Press and hold the ignition in Start  position. Observe voltmeter. If reading is above 0.2 volt, correct poor starter to engine block ground contact. Note: Certain diesel equipped models use dual batteries. If equipped with dual battery system, this procedure must be performed on driver side battery only. 
  6. If equipped with dual battery system (certain diesel equipped models), connect positive lead of voltmeter to positive battery cable clamp on battery located on left side of vehicle. Connect negative lead of voltmeter to positive battery terminal post on battery located on right side of vehicle. Press and hold the ignition in Start  position. Observe voltmeter. If reading is above 0.2 volt, clean and tighten battery cables at both batteries. Repeat test. If reading is still above 0.2 volt, replace faulty positive battery cable.

    If resistance tests detect no feed circuit problems, refer to STANDARD STARTING SYSTEM  in the Diagnosis and Testing.