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Home >> Saturn >> 2006 >> Ion Red Line >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - DTC P1682 To DTC P2229 >> DTC P2135 >> Test Description
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Test Description

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

  1. 6:  This step tests the integrity of the 5-volt reference and ground circuits of the TP sensors.
  2. 7:  This step determines if the 5-volt reference circuit or the sensor ground circuit is the cause of the DTC.
  3. 8:  If the scan tool displays 100 percent for the TP sensor 1 and the TP sensor 2 angle, this indicates that the TP sensor signal circuits are not the cause of the DTC.
  4. 9:  This step tests for excessive resistance in the TP sensor 5-volt reference circuit between the TP sensor harness connector and the PCM harness connector.
  5. 10:  This step tests for excessive resistance in the TP sensor ground circuit between the TP sensor harness connector and the PCM harness connector.
  6. 11:  This step tests for the TP sensor signal circuits for being shorted to another circuit in the PCM wiring harness between the PCM and the TP sensor wiring harness.
  7. 16:  When the PCM detects a problem within the throttle control system, more than one related DTC may set. This is due to the many redundant tests run continuously on this system. Locating and repairing one individual problem may correct more than one DTC. Keep this in mind when reviewing captured DTC info.
DTC P2135

Step Action Value(s) Yes No
Schematic Reference: Engine Controls Schematics
Connector End View Reference: Engine Controls Connector End Views or Powertrain Control Module (PCM) Connector End Views
1 Did you perform the Diagnostic System Check - Vehicle? - Go to Step 2  Go to Diagnostic System Check - Vehicle
2 Observe the DTC information with a scan tool.
Is DTC P0641 or P0651 also set?		 - Go to Diagnostic Trouble Code (DTC) List - Vehicle Go to Step 3 
3
  1. Turn ON the ignition, with the engine OFF.
  2. Monitor the TP sensors Agree/Disagree parameter using the scan tool.
Does the scan tool indicate Disagree?		 - Go to Step 6  Go to Step 4 
4
  1. Remove the resonator assembly from the throttle body assembly.
    2. IMPORTANT: Removing the ECM/ETC fuse will set additional DTCs.
  2. Remove the 15 A ECM fuse.
  3. Open the throttle blade to wide open throttle (WOT) by hand and then return it to closed throttle. Stop briefly at approximately 25 percent, 50 percent, 75 percent and 100 percent in each direction. Test the Throttle Sensors Disagree parameter at each stop.
Does the scan tool indicate Disagree while rotating the throttle blade?		 - Go to Step 6  Go to Step 5 
5
  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.
Does the DTC fail this ignition?		 - Go to Step 15  Go to Testing for Intermittent Conditions and Poor Connections
6 
  1. Disconnect the throttle position (TP) sensor electrical connector.
  2. Turn ON the ignition, with the engine OFF.
  3. Measure the voltage between the 5-volt reference circuit of TP sensor 1 and the TP sensor 1 low reference circuit with a DMM.
  4. Measure the voltage between the 5-volt reference circuit of TP sensor 2 and the TP sensor 2 low reference circuit with a DMM.
Does the DMM display a voltage within the specified range for both measurements?		 4.9-5.1 V Go to Step 8  Go to Step 7 
7  Test the voltage on the 5-volt reference circuit for TP sensor 1 and TP sensor 2 to a battery ground with a DMM.
Does the DMM display a voltage within the specified range?		 4.9-5.1 V Go to Step 10  Go to Step 9 
8  Observe the TP sensor 1 and TP sensor 2 angle on the scan tool.
Does the scan tool indicate both sensors at the specified value?		 100% Go to Step 12  Go to Step 11 
9  Test the 5-volt reference circuit of the TP sensor 1 and TP sensor 2 for high resistance. Refer to Circuit Testing and Wiring Repairs .
Did you find and correct the condition?		 - Go to Step 15  Go to Step 13 
10  Test the low reference circuit of the TP sensor 1 and TP sensor 2 for high resistance. Refer to Circuit Testing and Wiring Repairs .
Did you find and correct the condition?		 - Go to Step 15  Go to Step 13 
11  Test the signal circuit of the TP sensor 1 and TP sensor 2 for high resistance.
Did you find and correct the condition?		 - Go to Step 15  Go to Step 13 
12 Replace the throttle body assembly. Refer to Throttle Body Assembly Replacement .
Did you complete the replacement?		 - Go to Step 15  -
13 Test for poor connections and/or terminal tension at the TP sensor and at the powertrain control module (PCM). Refer to Testing for Intermittent Conditions and Poor Connections .
Did you find and correct the condition?		 - Go to Step 15  Go to Step 14 
14 Replace the PCM. 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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