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Home >> Chevrolet >> 2006 >> Impala SS >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - 5.3L - DTC P0449 To DTC P1516 >> DTC P0557 >> Test Description
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Test Description

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

  1. 7:  This step is measuring the current flow of the 5-volt reference circuit from the ECM.
DTC P0557

Step Action Values Yes No
Schematic Reference: Engine Controls Schematics
Connector End View Reference: Engine Control Module (ECM) Connector End Views and Engine Controls Connector End Views
1 Did you perform the Vehicle System Check - Vehicle? - Go to Step 2  Go to Diagnostic System Check - Vehicle
2 Observe the brake booster pressure sensor voltage parameter with a scan tool.
Is the brake booster pressure sensor voltage parameter less than the specified value?		 0.05 V Go to Step 4  Go to Step 3 
3
  1. Observe the Freeze Frame/Failure Records for this DTC.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Is the brake booster pressure sensor voltage parameter less than the specified value?		 0.05 V Go to Step 4  Go to Testing for Intermittent Conditions and Poor Connections
4 Is DTC P0641 also set? - Go to Diagnostic Trouble Code (DTC) List - Vehicle Go to Step 5 
5
  1. Turn OFF the ignition.
  2. Disconnect the brake booster pressure sensor wire harness electrical connector.
  3. Test for shorted terminals and poor connections at the brake booster pressure sensor wire harness electrical connector and also the mating electrical connector on the brake booster pressure sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .
Did you find and correct the condition		 - Go to Step 15  Go to Step 6 
6
  1. Turn ON the ignition with the engine OFF.
  2. Measure the voltage from the 5-volt reference circuit at the brake booster pressure sensor wire harness electrical connector to a good ground with a DMM. Refer to Circuit Testing .
Is the voltage within the specified range?		 4.8-5.2 V Go to Step 7  Go to Step 9 
7 
  1. Turn OFF the ignition.
  2. Connect one test lead of the DMM to the 5-volt reference circuit at the brake booster sensor wire harness electrical connector.
  3. Connect the other test lead of the DMM to a good ground.
  4. Configure the DMM to measure on the milliamps scale. Refer to Circuit Testing .
  5. Turn ON the ignition with the engine OFF.
Is the amperage less than the specified value?		 174 mA Go to Step 9  Go to Step 8 
8
  1. Turn ON the ignition with the engine OFF.
  2. Connect a 3-amp fused jumper wire between the 5-volt reference circuit of the brake booster pressure sensor, and the signal circuit of the brake booster pressure sensor.
  3. Observe the brake booster pressure sensor voltage parameter with a scan tool.
Is the brake booster pressure sensor voltage parameter within the specified range?		 4.8-5.2 V Go to Step 13  Go to Step 10 
9 Test the brake booster pressure sensor 5-volt reference circuit for the following conditions:
  • An open
  • High resistance
  • A short to ground

Refer to Circuit Testing and Wiring Repairs .
Did you find and correct the condition?		 - Go to Step 15  Go to Step 12 
10 Test the brake booster pressure sensor signal circuit for the following conditions:
  • An open
  • High resistance
  • A short to ground

Refer to Circuit Testing and Wiring Repairs .
Did you find and correct the condition?		 - Go to Step 15  Go to Step 11 
11 Test the brake booster pressure sensor low reference circuit for the following conditions:
  • An open
  • High resistance

Refer to Circuit Testing and Wiring Repairs .
Did you find and correct the condition?		 - Go to Step 15  Go to Step 12 
12 Test for shorted terminals and poor connections at the engine control module (ECM) wire harness electrical connectors. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .
Did you find and correct the condition?		 - Go to Step 15  Go to Step 14 
13 Replace the brake booster pressure sensor. Refer to Brake Booster Vacuum Sensor Replacement .
Did you complete the replacement?		 - Go to Step 15  -
14 Replace the ECM. Refer to Control Module References for replacement, setup, and programming.
Did you complete the replacement?		 - Go to Step 15  -
15
  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition?		 - Go to Step 2  Go to Step 16 
16 Observe the Capture Info with a scan tool.
Are there any DTCs that have not been diagnosed?		 - Go to Diagnostic Trouble Code (DTC) List - Vehicle System OK
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