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Home >> Cadillac >> 2004 >> Escalade EXT >> Repair and Diagnosis >> Electrical >> Charging Systems >> Battery, Charging System And Starting System >> Diagnostic Information and Procedures >> DTC P0615: Starter Relay Control Circuit >> Test Description
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Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. 2:  Listen for an audible click when the Start 1 relay operates. Turn the ignition switch back and forth from the ON to START positions. Repeat this as necessary.
  2. 3:  Tests for voltage at the coil side of the Start 1 relay. The PCM IGN fuse supplies power to the coil side of the Start 1 relay.
  3. 4:  Verifies that the PCM is providing ground to the Start 1 relay.
  4. 5:  Tests if ground is constantly being applied to the Start 1 relay.
DTC P0615

Step Action Yes No
Schematic Reference: Starting and Charging Schematics 
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. Turn ON the ignition, with the engine OFF.
  3. Turn the ignition back and forth from the ON to START positions.
Does the Start 1 relay turn ON and OFF with each command?		 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 Start 1 relay.
  3. Turn ON the ignition, with the engine OFF.
  4. Probe the battery positive voltage of the Start 1 relay coil circuit with a test lamp that is connected to a good ground.
Does the test lamp illuminate?		 Go to Step 4  Go to Step 8 
4 
  1. Connect a test lamp between the control circuit of the Start 1 relay and the battery positive voltage of the Start 1 relay coil circuit.
  2. Turn the ignition back and forth from the ON to START positions.
Does the test lamp turn ON and OFF with each command?		 Go to Step 6  Go to Step 5 
5  Test the control circuit of the Start 1 relay for a short to voltage or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 Go to Step 11  Go to Step 7 
6 Inspect for poor connections at the Start 1 relay. 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 11  Go to Step 9 
7 Inspect for poor connections at the 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 11  Go to Step 10 
8 Repair the battery positive voltage circuit of the Start 1 relay. Refer to Connector Repairs in Wiring Systems.
Did you complete the repair?		 Go to Step 11  -
9 Replace the Start 1 relay. Refer to Relay Replacement (Within an Electrical Center) or Relay Replacement (Attached to Wire Harness) in Wiring Systems.
Did you complete the replacement?		 Go to Step 11  -
10
IMPORTANT: The replacement PCM must be programmed.
Replace the PCM. Refer to Powertrain Control Module (PCM) Replacement in Engine Controls.Did you complete the replacement?		 Go to Step 11  -
11
  1. Review and record the scan tool Fail Records data.
  2. Use the scan tool in order to clear the DTC.
  3. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
  4. Using the scan tool, observe the Specific DTC Information for DTC P0615 until the test runs.
Does the scan tool indicate that DTC P0615 failed this ignition?		 Go to Step 2  System OK
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