well my gf just called me up saying the service engine light came on our 2004.5 dmax truck. she said it still feels fine, what would you guys suggest i do first? ima take it to my friends house and have him scan for codes or what not but what do u guys think might be off the top of ur guys head? thanks for the help
LLY: service engine light
- Thread starter 59 camaro
- Start date
Could be one of about one million possibilities, pull the code(s) and then post again. Chances are its something minor.
Most CEL's are emission sensor related codes, like MAF codes.
If it runs fine, don't sweat it. Drive it until you can scan it.
If I never see a CEL on my trucks, that's when I worry...
If it runs fine, don't sweat it. Drive it until you can scan it.
If I never see a CEL on my trucks, that's when I worry...
Glow Plug Module
Sounds like a glow plug or the module needs replaced. I would lean towards a glow plug is bad. I'll let the experts take over from here.
Sounds like a glow plug or the module needs replaced. I would lean towards a glow plug is bad. I'll let the experts take over from here.
No expert here but odds are the glow plug control module bought the farm, I,m no good at posting the GM info but the dtc flow chart for po670 might be here already check all the glow plugs while your there. Retail on the modules are like $180 IIRC.
Document ID: 1398955
DTC P0670
Circuit Description
The glow plug controller has the ability to perform internal diagnostics for voltage and output state of the glow plugs. If the glow plug controller senses an open in the main battery supply to the glow plug controller, or a condition with any of the glow plug driver circuits, the glow plug controller will send an error message to the engine control module (ECM).
DTC Descriptor
This diagnostic supports the following DTC:
DTC P0670 Glow Plug Module Control Circuit
Conditions for Running the DTC
• DTC U0073 or U0106 is not set.
• The ignition is ON.
Conditions for Setting the DTCThe glow plug controller detects an open to the main battery supply for the glow plugs, or an open in all 8 glow plug circuits.
Action Taken When the DTC Sets
• The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
• The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.
Conditions for Clearing the MIL/DTC• The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
• A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
• A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
• Clear the MIL and the DTC with a scan tool.
StepAction
Values
Yes
No
Schematic Reference: Engine Controls Schematics
1
Did you perform the Diagnostic System Check - Engine Controls?
--
Go to Step 2
Go to Diagnostic System Check - Engine Controls
2
- 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 DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
--
Go to Step 3
Go to Intermittent Conditions
3
Is DTC P0671-P0678 set?
--
Go to Step 4
Go to Step 5
4
Important: The DMM and test leads must be calibrated to 0 ohms in order to prevent misdiagnosis. Use the DMM to perform this test. Refer to the DMM User Manual for calibration procedure.
- Turn OFF the ignition.
- Disconnect the glow plug controller harness connector.
- Measure the resistance from the ground circuit at the glow plug controller harness connector and a good ground on the engine with a DMM.
1 Ω
Go to Step 6
Go to Step 7
5
- Turn OFF the ignition.
- Disconnect the main battery circuit from the glow plug controller.
- Probe the main battery circuit with a test lamp that is connected to a good ground. Refer to Probing Electrical Connectorsin Wiring Systems.
--
Go to Step 6
Go to Step 8
6
Test for an intermittent and for a poor connection at the harness connector of the glow plug controller. 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 11
Go to Step 10
7
Repair the ground circuit of the glow plug harness between the glow plug controller and the engine ground for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you complete the repair?
--
Go to Step 9
--
8
Repair the openor short to ground in the pattery positive voltage circuit between the glow plug controller and the battery.
Did you complete the repair?
--
Go to Step 11
--
9
Replace the glow plugs. Refer to Glow Plug Replacement - Bank 1 and Glow Plug Replacement - Bank 2.
Did you complete the replacement?
--
Go to Step 11
--
10
Replace the glow plug controller. Refer to Glow Plug Controller Replacement.
Did you complete the replacement?
--
Go to Step 11
--
11
- Clear the DTCs with a scan tool.
- Turn OFF the ignition for 30 seconds.
- Start the engine.
- 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.
--
Go to Step 2
Go to Step 12
12
Observe the Capture Info with a scan tool.
Are there any DTCs that have not been diagnosed?
--
Go to Diagnostic Trouble Code (DTC) List
System OK
© 2011 General Motors. All rights reserved.
Document ID: 1374765
Engine Data Sensors - Glow Plug Controls
© 2011 General Motors. All rights reserved.
Did they try clearing the code if so did it come back on? Some guys in warmer areas run without glow plugs. I would check all the glow plugs to make sure something stupid did not happen as simple as the wire coming off the glow plug also check and make sure the the wire intop of the glow plug controler did not come lose.