FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Battery Cable: Testing and Inspection

A voltage drop test will determine if there is excessive resistance in the battery cable terminal connections or the battery cable If excessive resistance is found in the battery cable connections, the connection point should be disassembled, cleaned of all corrosion or foreign material, then reassembled Following reassembly, check the voltage drop for the battery cable connection and the battery cable again to confirm repair

When performing the voltage drop test, it is important to remember that the voltage drop is giving an indication of the resistance between the two points at which the voltmeter probes are attached EXAMPLE When testing the resistance of the battery positive cable, touch the voltmeter leads to the battery positive cable terminal clamp and to the battery positive cable eyelet terminal at the starter solenoid B(+) terminal stud If you probe the battery positive terminal post and the battery positive cable eyelet terminal at the starter solenoid B(+) terminal stud, you are reading the combined voltage drop in the battery positive cable terminal cl amp-to-term in all post connection and the battery positive cable

VOLTAGE DROP TEST
The following operation will require a voltmeter accurate to 1/10 (0 10) volt Before performing this test, be certain that the following procedures are accomplished
- The battery is fully-charged and load tested
- Fully engage the parking brake
- If the vehicle is equipped with an automatic transmission, place the gearshift selector lever in the Park position If the vehicle is equipped with a manual transmission, place the gearshift selector lever in the Neutral position and block the clutch pedal in the fully depressed position
- Verify that all lamps and accessories are turned off
- To prevent the engine from starting, remove the Automatic Shut Down (ASD) relay The ASD relay is located in the Power Distribution Center (PDC), in the engine compartment See the fuse and relay layout label affixed to the underside of the PDC cover for ASD relay identification and location

Test Battery Negative Connection Resistance - Typical:




1. Connect the positive lead of the voltmeter to the battery negative terminal post Connect the negative lead of the voltmeter to the battery negative cable terminal clamp Rotate and hold the ignition switch in the Start position Observe the voltmeter If voltage is detected, correct the poor connection between the battery negative cable terminal clamp and the battery negative terminal post

Test Battery Positive Connection Resistance - Typical:




2. Connect the positive lead of the voltmeter to the battery positive terminal post Connect the negative lead of the voltmeter to the battery positive cable terminal clamp Rotate and hold the ignition switch in the Start position Observe the voltmeter If voltage is detected, correct the poor connection between the battery positive cable terminal clamp and the battery positive terminal post

Test Battery Positive Cable Resistance - Typical:




3. Connect the voltmeter to measure between the battery positive cable terminal clamp and the starter solenoid B(+) terminal stud Rotate and hold the ignition switch in the Start position Observe the voltmeter If the reading is above 0 2 volt, clean and tighten the battery positive cable eyelet terminal connection at the starter solenoid B(+) terminal stud. Repeat the test. If the reading is still above 0.2 volt, replace the faulty battery positive cable.

Test Ground Circuit Resistance - Typical:




4. Connect the voltmeter to measure between the battery negative cable terminal clamp and a good clean ground on the engine block. Rotate and hold the ignition switch in the Start position. Observe the voltmeter. If the reading is above 0.2 volt, clean and tighten the battery negative cable eyelet terminal connection to the engine block. Repeat the test. If the reading is still above 0.2 volt, replace the faulty battery negative cable.