DTC P0135 or P0155Step
Action
Value(s)
Yes
No
Schematic Reference: Engine Controls Schematics
Connector End View Reference: Engine Controls Component Views or Powertrain Control Module Connector End Views
1
Did you perform the Diagnostic System Check?Engine Controls?
?
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Step 2
Go to
Diagnostic System Check - Engine Controls
2
Important: Whenever the HO2S heaters are commanded ON with a scan tool, they will continue to be pulsed ON once per second until the ignition is turned OFF for 30 seconds.
- Turn ON the ignition, with the engine OFF.
- Command the HO2S heaters ON with a scan tool.
- Wait 15 seconds to allow the HO2S heater current to stabilize.
- Observe the affected HO2S heater current parameter with a scan tool.
Is the HO2S heater current parameter within the specified range?
0.25?3.125 A
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Step 3
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Step 6
3
Observe the Freeze Frame/Failure Records for this DTC.
Did the DTC fail with an engine run time of less that 10 seconds?
?
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Step 4
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Step 5
4
- Operate the vehicle within the Conditions for Running the Heater Resistance Test.
- Start the engine.
Did the DTC fail this ignition?
?
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Step 6
Go to
Intermittent Conditions
5
- Observe the Freeze Frame/Failure Records for this DTC.
- Turn OFF the ignition for 30 seconds.
- Start the engine.
- Operate the vehicle within the Conditions for Running the Heater Current Test. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition?
?
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Step 6
Go to
Intermittent Conditions
6
Inspect the O2A fuse.
Is the O2A fuse open?
?
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Step 7
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Step 8
7
Test the ignition 1 voltage circuit for a short to ground. Refer to
Circuit Testing and
Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
?
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Step 22
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Step 10
8
- Disconnect the affected HO2S.
- Turn ON the ignition, with the engine OFF.
- Probe the ignition 1 voltage circuit of the HO2S harness connector on the engine harness side with a test lamp that is connected to a good ground. Refer to Probing Electrical Connectors in Wiring Systems.
Does the test lamp illuminate?
?
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Step 9
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Step 19
<a id="td09_rev"><a href="http://gsi.xw.gm.com/newsi/showDoc.do?docSyskey=1250611&cellId=66527&pubObjSy skey=3144813&from=sm&pubCellSyskey=642081&delivery EffectiveDate=May+1%2C+2013#td09">
9
Important: The test lamp may blink prior to commanding the heaters ON. This is because the heaters were commanded ON in a previous step. To command the heaters OFF, turn OFF the ignition for 30 seconds.
- Connect a test lamp between the ignition 1 voltage circuit of the HO2S harness connector on the engine harness side and the HO2S heater low control circuit of the HO2S harness connector on the engine harness side.
- Command the HO2S heaters ON with a scan tool.
Does the test lamp blink once per second?
?
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Step 11
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Step 12
10
Important: Perform the following test on all HO2S' which are supplied voltage by the suspect circuit.
Test the ignition 1 voltage circuit on the sensor side of the HO2S connector for a short to ground. Refer to
Circuit Testing in Wiring Systems.
Is any sensor shorted to ground?
?
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Step 20
Go to
Intermittent Conditions
11
Measure the resistance of the following circuits with a DMM:
- HO2S heater low control circuit
- Ignition 1 voltage circuit
Refer to
Circuit Testing in Wiring Systems.
Is the resistance of either circuit more than the specified value?
3 Ω
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Step 18
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Step 16
12
Is the test lamp on steady?
?
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Step 13
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Step 14