LEMON Manuals: Even more car manuals for everyone
Home >> GMC >> 2003 >> Safari Van Cargo, AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 1039 (Battery, Charging System And Starting System Diagnosis (DTC B1327-DTC P1638)) >> Diagnosis >> DTC P1637 >> Conditions for Clearing the MIL/DTC

Conditions for Clearing the MIL/DTC

WARNING: This page is about a different car, the 2004 GMC Sierra, 2004 GMC Cab & Chassis Sierra, 2004 Chevrolet Silverado, and 2004 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
DTC P1637

Step Action Value Yes No
Schematic Reference: Starting and Charging Schematics (Except HP2) or Starting and Charging Schematics (HP2)
Connector End View Reference: Engine Electrical Connector End Views
1 Did you perform the Engine Electrical Diagnostic System Check? - Go to Step 2  Go to Diagnostic System Check - Engine Electrical
2
  1. Install a scan tool.
  2. Start the engine.
  3. With a scan tool, monitor the DTC information for DTC P1637 in Engine Controls.
Does the scan tool indicate that DTC P1637 has passed?		 - Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems Go to Step 3 
3
  1. Turn OFF the ignition.
  2. Disconnect the generator harness connector.
  3. Start the engine and let idle.
  4. Measure the voltage between the generator turn on signal circuit and ground.
Does the voltage measure near the specified value?		 10-11 volts. Go to Step 5  Go to Step 4 
4 Test the generator turn on signal circuit for a short or open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 8  Go to Step 6 
5 Inspect for poor connections at the harness connector of the generator. Refer to Connector Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 8  Go to Charging System Test (CS/AD/SI Generators)
6 Inspect for poor connections at the harness connector of the powertrain control module (PCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 8  Go to Step 7 
7
IMPORTANT: The replacement PCM must be programmed.
Replace the PCM/engine control module (ECM). Refer to Powertrain Control Module (PCM) Replacement in Engine Controls - 4.3L, Powertrain Control Module (PCM) Replacement in Engine Controls - 4.8L/5.3L/6.0L, Powertrain Control Module (PCM) Replacement in Engine Controls - 8.1L, or Engine Control Module (ECM) Replacement in Engine Controls - 6.6L.Is action complete?		 - Go to Step 8  -
8
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
Does the DTC reset?		 - Go to Step 2  System OK
scientia non olet · About LEMON Manuals