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Home >> Cadillac >> 2007 >> Escalade EXT >> Repair and Diagnosis >> External Pages >> Different car >> Section 407 (Engine Cooling System) >> Diagnostic Information and Procedures >> DTC P1A87: Low Starter/Generator Control Module Coolant Level >> Diagnostic Aids
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Diagnostic Aids

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.

If the vehicle is on an extreme angle this DTC may set.

DTC P1A87

Step Action Yes No
Schematic Reference: Engine Cooling Schematics 
Connector End View Reference: Cooling System Connector End Views 
1 Was the Engine Cooling Diagnostic System Check performed? Go to Step 2  Go to Diagnostic System Check - Engine Cooling 
2
  1. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
  2. With a scan tool, observe the SGCM DTC list.
Is the DTC set as current DTC?		 Go to Step 3  Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems
3
IMPORTANT: Perform the programming procedure for the SGCM.
Replace the SGCM. Refer to Starter/Generator Control Module (SGCM) Replacement (5.3L Engine w/RPO HP2) in Engine Electrical.Did you complete the replacement?		 Go to Step 4  -
4
  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
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