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Home >> Cadillac >> 2005 >> XLR >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls (DTC P0010 To P0153) >> DTC P0118 >> Test Description
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Test Description

The number below refers to the step number on the diagnostic table.

  1. 7:  This step tests for the proper operation of the circuit in the low voltage range.
DTC P0118

Step Action Values Yes No
Schematic Reference: Engine Controls Schematics
Connector End View Reference: Engine Controls Connector End Views or Engine Control Module (ECM) Connector End Views
1 Did you perform the Diagnostic System Check - Vehicle? - Go to Step 2  Go to Diagnostic System Check - Vehicle in Vehicle DTC Information
2 Are DTCs P0641 or P0651 set? - Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information Go to Step 3 
3
IMPORTANT: The cooling fans are commanded ON when certain DTCs are set.
Observe the ECT Sensor parameter with a scan tool.Is the ECT Sensor parameter less than the specified value?		 -39°C (-38°F) Go to Step 5  Go to Step 4 
4
  1. Observe the Freeze Frame/Failure Records for this DTC.
  2. Turn OFF the ignition for 60 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 5  Go to Inducing Intermittent Fault Conditions in Wiring Systems and Intermittent Conditions
5
  1. Disconnect the engine coolant temperature (ECT) sensor.
  2. Measure the voltage from the signal circuit of the ECT sensor to a good ground with a DMM. Refer to Probing Electrical Connectors and Circuit Testing in Wiring Systems.
Is the voltage more than the specified value?		 5.2 V Go to Step 6  Go to Step 7 
6
IMPORTANT: If a short to voltage occurs, the ECT sensor may be damaged.
Test the ECT signal circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.Did you find and correct the condition?		 - Go to Step 16  Go to Step 13 
7 
  1. Connect a 3-amp fused jumper wire between the signal circuit of the ECT sensor and the low reference circuit of the ECT sensor. Refer to Using Fused Jumper Wires in Wiring Systems.
  2. Observe the ECT Sensor parameter with a scan tool.
Is the ECT Sensor parameter more than the specified value?		 138°C (280°F) Go to Step 11  Go to Step 8 
8
  1. Connect a 3-amp fused jumper wire between the signal circuit of the ECT sensor and a good ground.
  2. Observe the ECT Sensor parameter with a scan tool.
Is the ECT Sensor parameter more than the specified value?		 138°C (280°F) Go to Step 10  Go to Step 9 
9 Test the ECT signal circuit for a high resistance or for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 16  Go to Step 13 
10 Test the ECT low reference circuit for a high resistance or for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 16  Go to Step 13 
11
IMPORTANT: If a short to voltage occurs, this DTC may set and damage the ECT sensor.
Test the signal circuit of the ECT sensor for a short to any 5-volt reference circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.Did you find and correct the condition?		 - Go to Step 16  Go to Step 12 
12 Test for an intermittent and for a poor connection at the ECT sensor. Refer to Testing for Intermittent Conditions and Poor Connections , Repairing Connector Terminals , and Connector Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 16  Go to Step 14 
13 Test for an intermittent and for a poor connection at the engine control module (ECM). Refer to Testing for Intermittent Conditions and Poor Connections , Repairing Connector Terminals , and Connector Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 16  Go to Step 15 
14 Replace the ECT sensor. Refer to Engine Coolant Temperature (ECT) Sensor Replacement .
Did you complete the replacement?		 - Go to Step 16  -
15 Replace the ECM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.
Did you complete the replacement?		 - Go to Step 16  -
16
  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 60 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 17 
17 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 in Vehicle DTC Information System OK
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