Battery Cable: Testing and Inspection

DIAGNOSIS AND TESTING - BATTERY CABLES

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 clamp-to-terminal 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, Battery Charging for the proper battery charging procedure.
- The battery has successfully passed a load test, Battery Charging for the proper load test procedure.
- 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.





1. Remove the spare tire cover to gain access to the battery. 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. Press and hold the ignition button 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.





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. Press and hold the ignition button 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.





3. Using a suitable jumper wire, connect the voltmeter to measure between the battery negative cable terminal clamp and a good clean ground on the engine block. Press and hold the ignition button 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 at the transmission housing. Repeat the test. If the reading is still above 0.2 volt, perform 4 and 5.





4. Connect the voltmeter to measure between the battery negative cable terminal clamp and the battery negative cable eyelet terminal connection at the vehicle body. Press and hold the ignition button 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 at the vehicle body. Repeat the test. If the reading is still above 0.2 volt, replace the battery rear negative cable, Battery Cables - Removal.





5. Connect the voltmeter to measure between the battery negative cable eyelet terminal connection at the right front strut tower and the battery negative cable eyelet terminal connection at the transmission housing. press and hold the ignition button 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 at the right front strut tower. Repeat the test. If the reading is still above 0.2 volt, replace the battery front negative cable, Battery Cables - Removal.





6. Using a suitable jumper wire, connect the voltmeter to measure between the battery positive cable terminal clamp and the starter solenoid B(+) terminal stud. Press and hold the ignition button 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, perform 7 and 8.





7. Remove the right front wheelhouse splash shield to gain access to the battery positive cable bulkhead outside terminal, Splash Shield - Removal. Connect the voltmeter to measure between the battery positive cable bulkhead outside terminal and the starter solenoid B(+) terminal stud. press and hold the ignition button in the Start position. Observe the voltmeter. If the reading is above 0.2 volt, clean and tighten the battery positive cable bulkhead outside terminal connection. Repeat the test. If the reading is still above 0.2 volt, replace the battery front positive cable, Battery Cables - Removal.





8. Remove the right front carpet to gain access to the battery positive cable bulkhead inside terminal. Connect the voltmeter to measure between the battery positive cable terminal clamp and the battery positive cable bulkhead inside terminal connection. press and hold the ignition button in the Start position. Observe the voltmeter. If the reading is above 0.2 volt, clean and tighten the battery positive cable bulkhead inside terminal connection. Repeat the test. If the reading is still above 0.2 volt, replace the battery rear positive cable, Battery Cables - Removal.