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Test Ch-1A - Charging System No Code

WARNING: This page is about a different car, the 1995 Dodge Ram Wagon, 1995 Dodge Ram Van, 1995 Dodge Pickup, and 1995 Dodge Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
CAUTION: If battery shows signs of freezing or leakage, battery posts are loose or battery has low electrolyte level, DO NOT  test.
NOTE: Perform TEST TC-1A before proceeding. Perform TEST CH-VER after repairs are made.
  1. Verify battery is in good condition. Inspect generator belt tension and condition. Replace belt if necessary.
  2. Start engine. Using DRB, set engine speed at 2000 RPM for 30 seconds. Return engine speed to idle, and read fault codes. If fault codes exist, go to appropriate test. See DRB FAULT MESSAGES  table under TEST TC-1A. If there are no fault codes, turn engine off, but leave ignition on. Using DRB, actuate generator field.
  3. With DRB in voltmeter mode, backprobe field driver terminal (Dark Green or Dark Green/White wire) on back of generator. See Figure. Ensure voltage cycles from zero to battery voltage every 1.4 seconds.
  4. Observe DRB display, and wiggle wiring harness from generator field terminals to PCM and ASD relay. If normal cycling of voltage is interrupted, repair appropriate wire. If voltage cycling is not interrupted, go to next step.
  5. Check for fault codes using DRB. If fault codes exist, perform appropriate test. See DRB FAULT MESSAGES  table under TEST TC-1A. If there are no fault codes, connect positive lead of external voltmeter to generator B+ terminal, and negative lead to positive battery terminal. See Figure. Ensure all wires are clear of engine's moving parts.
  6. Start engine and note voltmeter reading. If voltage is 0.4 volt or less, go to next step. If voltage is greater than 0.4 volt, repair high resistance condition in power circuit between generator B+ terminal and battery.
  7. Turn ignition off. Connect positive lead of external voltmeter to generator case, and negative lead to negative battery terminal. Ensure all wires are clear of engine's moving part. Start engine and note reading on voltmeter. If voltage is 0.1 volt or less, go to next step. If voltage is greater than 0.1 volt, repair high resistance condition in ground circuit between generator and battery.
  8. Using DRB, read battery voltage. Measure voltage across battery terminals using external voltmeter. Compare the 2 voltage readings. If voltage difference is greater than one volt, go to next step. If voltage difference is less than one volt, test is complete.
  9. Disconnect PCM. Clean and repair connector as necessary. With DRB in voltmeter mode, probe PCM connector terminal No. 3. See Figure. If voltage is within one volt of DRB voltage reading obtained in step 8), repair high resistance condition in circuit between PCM connector terminal No. 3 and battery. If voltage is not within one volt of previous DRB voltage reading, replace PCM.
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