Engine Controls and Fuel - 3.0L LM2 Diesel | Diagnostic Information and Procedures | Document ID: 5501104
Diagnostic Instructions
Perform the Diagnostic System Check prior to using this diagnostic procedure: Diagnostic
System Check - Vehicle
Review the description of Strategy Based Diagnosis: Strategy Based Diagnosis
An overview of each diagnostic category can be found here: Diagnostic Procedure
Instructions
DTC Descriptor
DTC P161E
Glow Plug Supply Voltage Circuit
Diagnostic Fault Information
| Circuit |
Short to Ground |
Open/High Resistance |
Short to Voltage |
Signal Performanc |
| B+ |
P161E |
P161E |
— |
— |
| Control — Cylinder 1 Glow Plug |
P066A |
P0671 |
P066B |
— |
| Control — Cylinder 2 Glow Plug |
P066C |
P0672 |
P066D |
— |
| Control — Cylinder 3 Glow Plug |
P066E |
P0673 |
P066F |
— |
| Control — Cylinder 4 Glow Plug |
P067A |
P0674 |
P067B |
— |
| Control — Cylinder 5 Glow Plug |
P067C |
P0675 |
P067D |
— |
| Control — Cylinder 6 Glow Plug |
P067E |
P0676 |
P067F |
— |
Circuit/System Description
For an overview of the component/system, refer to: Glow Plug System Description
| Circuit |
Description |
| B+ |
Supplied from a fuse. |
|
Component |
Description |
|
|
E12 Glow Plug |
Glow plugs are electric heating devices in the combustion chambers of diesel engines. |
|
|
K20 Engine Control Module |
The control module controls a series of actuators to ensure optimal engine performance. The control |
|
|
© 2023 General |
Mmootodrusl.e Adoll ersig thhtiss rbeys erervaeddin.g values from a variety of |
|
| Component |
Description |
|
sensors, interprets the data and adjusts the engine actuators accordingly. |
Conditions for Running the DTC
Ignition and Start Switch Signal = On
Engine cranking. = No
Ignition and Start Signal = Greater than 11 V
E12 Glow Plug = On
Frequency the DTC runs = Continuously — After the running conditions are met
Conditions for Setting the DTC
B+ circuit = Less than 6 V — Greater than 1 s
Actions Taken When the DTC Sets
DTC P161E = Type B DTC
Conditions for Clearing the DTC
DTC P161E = Type B DTC
Reference Information
Schematic Reference
Engine Controls Schematics
Connector End View Reference
Master Electrical Component List
Electrical Information Reference
Circuit Testing
Connector Repairs
Testing for Intermittent Conditions and Poor Connections
Wiring Repairs
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References
Circuit/System Verification
- Ignition » On / Vehicle » In Service Mode
- Verify DTC P161E is not set.
⇒ If the DTC is set
Refer to: Circuit/System Testing
- 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 data.
Verify the DTC does not set.
⇒ If the DTC sets
Refer to: Circuit/System Testing
⇓ If the DTC is not set
- All OK.
Circuit/System Testing
- Ignition/Vehicle & All vehicle systems » Off
- Disconnect the electrical connector: X1 @ K20 Engine Control Module
- Verify a test lamp turns On between the test points: B+ circuit terminal 1 & Ground
⇒ If the test lamp does not turn On and the circuit fuse is OK
3.1. Ignition/Vehicle » Off & Remove » Test lamp
3.2. Test for less than 2 Ω between the test points:
{ Escalade } B+ circuit terminal 1 & Output terminal @ F5UD Fuse
{ Sierra / Silverado / Tahoe / Yukon } B+ circuit terminal 1 & Output terminal @
F5BA Fuse
⇒ If 2 Ω or greater » Repair the open/high resistance in the circuit.
⇒ If less than 2 Ω » Verify the fuse is OK and there is voltage at the fuse.
⇒ If the test lamp does not turn On and the circuit fuse is open
3.1. Ignition/Vehicle » Off & Remove » Test lamp
3.2. Test for infinite resistance between the test points: B+ circuit terminal 1 & Ground
⇒ If less than infinite resistance » Repair the short to ground on the circuit.
⇒ If infinite resistance » Replace the component: K20 Engine Control Module
⇓ If the test lamp turns On
- Replace the component: K20 Engine Control Module
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair: Diagnostic Repair
Verification
For control module replacement, programming, and setup refer to: Control Module References