How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Jerry Newton Your Own Question
Jerry Newton
Jerry Newton, Chevy Technician
Category: Chevy
Satisfied Customers: 4752
Experience:  ASE Master Technician, L1, Master GM Technician. Over 20 years of bumper to bumper GM experience.
Type Your Chevy Question Here...
Jerry Newton is online now
A new question is answered every 9 seconds

2006 Chevy cobalt ls: intermittent..control module..position sensor

Customer Question

2006 Chevy cobalt ls 2.2l engine reduced power on screen, intermittent, throwing codes: p0641 sensor reference Voltage A circuit/open, P060E internal control module throttle position performance, P2138 throttle/pedal position sensor/switch D/E voltage correlation. Do I replace TPS? PPS?
Submitted: 5 years ago.
Category: Chevy
Expert:  Jerry Newton replied 5 years ago.
You have all of the symptoms described in this document from GM:

Subject:Intermittent SES Light due to DTCs P060E, P2135, and/or P2138

Models:2005-2007 Chevrolet Cobalt SS
2005-2008 Chevrolet Cobalt
2007-2008 Pontiac G5
2005-2006 Pontiac Pursuit (Canada Only)
2005-2007 Saturn Ion
2004-2007 Saturn Ion Redline
with any of the following engines:
2.0L Engine (VIN P - RPO LSJ)
2.2L Engine (VIN F - RPO L61)
2.4L Engine (VIN B - RPO LE5)

This PI was superseded to add a step for checking for a possible 5 volt reference concern. Please discard PIP4175D.

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.


On rare occasions, an intermittent SES light may be experienced due to DTCs P2135 and/or P2138. In some instances, a P060E may also be stored as a result of either DTC.


If any of the DTCs above are setting consistently, perform the SI diagnostics and repair as necessary. If the SI diagnostics do not isolate a cause for this concern due to the intermittent nature of this, perform the following suggestions as necessary:

1. Review the latest version of 07-06-04-003 and determine if it applies to the vehicle you are working on. If so, perform the bulletin and evaluate the concern. This bulletin relates to a potential ECM/PCM that can cause this concern on select vehicles and PCM build dates.
2. For P2138 DTCs, review the latest version of 07-06-04-019 and inspect corrosion or water intrusion in C201. Also inspect for a poor connection or poor terminal tension on the APP circuits while this connector is disconnected.
3. Inspect the engine harness for potential shorts to ground in the following locations, and repair and reposition the circuits/harness as necessary:
at the air conditioning line about 3-6 inches from the ECM/PCM connectors.
on the ECM/PCM case and/or on the edge of either ECM/PCM connector body.
at the air conditioning line bracket at the rear of the head, above the transmission.
at the edge of the aluminum oil filter housing on the engine block.
at the UBEC/UHJB bracket.
at the EVAP purge valve bracket.
at the rear of the cylinder head/upper edge of transmission bell housing.
Notice Since this PI is written for multiple models and engine RPOs, some of the locations listed above may not exist on certain model and engine RPO combinations. Inspect each location to determine which locations exist on the vehicle that you are working on and ensure that there are no shorts to ground present in these locations.
4. Inspect all of the APP (P2138) or TP (P2135) circuits to determine if duraseal splice sleeves were used during previous repairs, such as service pigtail harness installation. If so, the incorrect crimp tools may have been used to install the splice sleeves and this could be causing the concern. If the incorrect tools were used, or if it is unknown what tools were used to install the splice sleeves, replace the splice sleeves again by using the correct tools and following the "Splicing Copper Wire Using Splice Sleeves" Procedure in SI.
5. Test the battery by following the latest version of 02-06-03-009, and recharge or replace the battery as indicated on the tester. If the tester indicates "Good Battery", check for an excessive parasitic draw and for proper charging system operation, and repair as necessary. If there is no problem found with the battery or charging system, fully charge the battery and move on to Step 6 below.
6. Refer to the ECM/PCM Connector End Views in SI and inspect both ends of the circuits listed below for poor terminal tension. Use test probe J-35616-2A on the APP/TP sensor terminals and test probe J35616-64B on the ECM/PCM terminals. Also, inspect all of these circuits for high resistance or possible shorts to ground while wiggling the harness around. And, also inspect the connector face to ensure that none of the terminals have backed out and that the connector face cover is latched into position properly. If the connector face cover is not latched to the connector, it may become unfastened and stick in the sensor, preventing the connector from seating properly. If any concerns are found, repair as necessary by following SI procedures.
7. If any of the following DTCs are stored with the P2135 or P2138, there could be an issue with the 5 volt reference to the APP or TP sensor that is causing this concern:
P0097, P0098, P0101, P0102, P0103, P0106, P0107, P0108, P0111, P0112, P0113, P0116, P0117, P0118, P0335, P0336, P0340, P0341, P0451, P0452, P0453, P0454, P0461, P0462, P0463, P0464, P0532, P0533, P0641, P0651
If any of the DTCs above are stored, monitor the related 5 volt reference circuit when the concern occurs. If the 5 volt reference is lost when the concern occurs, unplug the related sensor to see if the 5 volt reference returns to normal. If it does, replace the related sensor and re-evaluate the concern. If the concern can not be verified to monitor the 5 volt reference and unplug the sensor during the concern, inspect all of the related circuits for possible shorts, inspect all of the related connectors for water or corrosion intrusion, and check the related sensor for proper operation and repair as necessary.
8. If there is no problem found above, follow SI procedures to remove the necessary terminals below from the ECM connector, re-crimp each terminal to each wire using the correct crimping tool called out in SI, and re-install them back into the correct ECM connector cavity. Once the repairs are complete, re-evaluate the concern.
For P2135 DTCs:
- Throttle Position Sensor (1) Signal (Ckt. 485)
- Throttle Position Sensor (2) Signal (Ckt. 486)
- Low Reference (Ckt. 2752)
- Low Reference (Ckt. 1704) *Note: 2007-2008 Models with the 2.2L Engine only have one low reference circuit. As a result, this circuit is not used on those models.
- 5 Volt Reference (Ckt. 2701)
- 5 Volt Reference (Ckt. 1688) *Note: 2007-2008 Models with the 2.2L Engine only have one 5 volt reference circuit. As a result, this circuit is not used on those models.
For P2138 DTCs:
- APP Sensor 1 Signal (Ckt. 1161)
- APP Sensor 2 Signal (Ckt. 1162)
- Low Reference (Ckt. 1271)
- Low Reference (Ckt. 1272)
- 5 Volt Reference (Ckt. 1164)
- 5 Volt Reference (Ckt. 1274)

Run through the list of things to check in that document before you replace anything.