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Test Description

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

  1. 2:  This step verifies that a condition exists.
  2. 4:  This step tests for a condition in the 5-volt reference circuit of the TP sensor. If the DMM does not display more than the specified voltage, test for a short to ground or an open in the 5-volt reference circuit.
  3. 5:  This step tests for a condition in the signal circuit of the TP sensor. If the TP Voltage parameter does not display more than the specified voltage, test for a short to ground or an open in the signal circuit.
Step Action Values Yes No
Schematic Reference:  Engine Controls Schematics 
Connector End View Reference:  Engine Control Module Connector End Views  or  Engine Controls Connector End Views 
1 Did you perform the Diagnostic System Check - Engine Controls? - Go to Step 2  Go to Diagnostic System Check - Engine Controls
2 
  1. Turn ON the ignition, with the engine OFF.
  2. Observe the throttle position (TP) sensor voltage parameter with a scan tool.
Is the voltage more than the specified value?		 0.2 V Go to Step 3  Go to Step 4 
3
  1. Turn OFF the ignition for 30 seconds.
  2. Start the engine.
  3. Operate the vehicle within the Conditions for Running the DTC.
Did the DTC fail this ignition?		 - Go to Step 4  Go to Intermittent Conditions
4 
  1. Turn OFF the ignition
  2. Disconnect the throttle body harness connector.
  3. Turn ON the ignition, with the engine OFF.
    4. IMPORTANT: Use the J 35616-200  Test Lamp Kit for this test. If the J 35616-200  is not available, use a test lamp that measures more than 20 ohms.
  4. Connect a test lamp between the 5-volt reference circuit of the throttle position (TP) sensor and the engine control module (ECM) housing.
  5. Connect a DMM to the probe of the test lamp and the ECM housing. Refer to Measuring Voltage Drop in Wiring Systems.
Is the voltage more than the specified value?		 4.8 V Go to Step 5  Go to Step 6 
5 
  1. Connect a 3-amp fused jumper wire between the 5-volt reference circuit of the TP sensor and the signal circuit of the TP sensor.
  2. Observe the TP sensor voltage parameter, with a scan tool.
Is the voltage less than the specified value?		 4.8 V Go to Step 7  Go to Step 8 
6
IMPORTANT: The 5-volt reference circuits are internally and externally connected at the controller. Other sensors that share the 5-volt reference circuit may also have DTCs set. Disconnecting a sensor on the shared 5-volt reference circuit may isolate a shorted sensor. Review the electrical schematic and diagnose the shared circuits and sensors.
Test the 5-volt reference circuit of the TP sensor and all shared 5-volt reference circuits for one of the following conditions:Did you find and correct the condition?		 - Go to Step 12  Go to Step 9 
7 Test the signal circuit of TP sensor for one of the following conditions:
Did you find and correct the condition?		 - Go to Step 12  Go to Step 9 
8 Test for an intermittent and for a poor connection at the throttle body assembly. 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 12  Go to Step 10 
9 Test for an intermittent and for a poor connection at the ECM. 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 12  Go to Step 11 
10 Replace the throttle body assembly. Refer to Throttle Body Assembly Replacement .
Did you complete the replacement?		 - Go to Step 12  -
11 Replace the ECM. Refer to Engine Control Module Replacement .
Did you complete the replacement?		 - Go to Step 12  -
12
  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.
Did the DTC fail this ignition?		 - Go to Step 2  Go to Step 13 
13 Are there any DTCs that have not been diagnosed? - Go to Diagnostic Trouble Code (DTC) List System OK
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