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Test Description

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

  1. 2:  This step checks the BPP sensor input voltage.
  2. 3:  This step checks for an open, short to B+ and short to ground in 5-volt reference circuit.
  3. 4:  This step tests for an open or short to ground in the BPP sensor 5-volt return circuit.
  4. 5:  This step test for an open or short to ground in the BPP sensor signal circuit.
  5. 6:  This step tests for a bad connection at the harness connector of the EHPS module.
DTC C0870

Step Action Yes No
Schematic Reference: Power Steering System Schematics 
Connector End Views Reference: Power Steering System Connector End Views 
1 Did you perform the electro-hydraulic power steering (EHPS) Diagnostic System Check? Go to Step 2  Go to Diagnostic System Check - Power Steering System 
2 
  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, observe the brake pedal position (BPP) sensor Input Voltage parameter in the EHPS control module data list.
Is the voltage reading less than 0 volts or greater than 5 volts?		 Go to Step 3  Go to Diagnostic Aids
3  Test the BPP sensor 5-volt reference circuit for one of the following conditions:
  • An open
  • A short to battery positive voltage
  • A short to ground

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 Go to Step 8  Go to Step 4 
4  Test the BPP sensor 5-volt return circuit for an open or a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 Go to Step 8  Go to Step 5 
5  Test the BPP sensor signal circuit for an open or a short to ground. Refer toCircuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 Go to Step 8  Go to Step 6 
6  Inspect for poor connections at the harness connector of the EHPS module. 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: Always perform the calibration procedure for the BPP sensor. Refer to Brake Pedal Position Sensor Calibration Description and Operation .
Replace the EHPS powerpack. Refer to Power Steering Pump Replacement (4.3L) Power Steering Pump Replacement (4.8L, 5.3L and 6.0L) Power Steering Pump Replacement (8.1L) Power Steering Pump Replacement (6.6L Diesel) Power Steering Pump Replacement (Parallel Hybrid Truck) .Did you complete the repair?		 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
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