Hey guys any help would be appreciated. Owned this 05 Silveroda 6.6 HD for 6 years ran great until month ago. Cranked it up and it shut off at stop sign? let it roll back in yard got code reader out got 1296....po405 and code that indicated fuel pressure regulator on injector pump going bad. Cleared codes .....ran perfect again? went ahead and replaced the fuel pressure regulator and seemed to run great again....drove it for 40 miles....thought I found the culprit and zap....went back into limp mode this time threw 1296...P0101.....p0405 p060...p1404and p1621.....back in Limp mode until I clear codes start it again and it runs perfect? besides the fuel pressure regulator changed the two connectors to the two front injectors that are problematic but starting to thing could be an issue with ECU.....any advice from seasoned owners would be appreciated....My neighbor put the truck on his scanner .....drove it around and watched the actual fuel rail pressure verses the desired and looked pretty consistent....Thanks Larry
2005 Silveroda 2500 HD 6.6 keeps going into Limp mode
- Thread starter lstill
- Start date
First off, let's look at the codes you posted and the description for each one.
None of these indicate the FPR was the issue.
The P0101, P0405, P1404 will all set when the EGR is not functioning correctly. It could also cause the vehicle to stall if its stuck open. Fix the EGR issue and see if the MAF code comes back.
The P1296 code indicates an issue with the FICM or the wiring going to it. The Diagnostic chart basically says it's an internal fault and to replace the FICM module.
The P1621 Could be an internal ECU fault but it could have something to do with how you are cycling the key and clearing the codes. I would look at your other issues first before condemning the ECU.
The other P060 is not a full code. The missing digit could indicate an ECU fault as well but we really need the correct code.
Here is the flow chart for the 1296 code.
None of these indicate the FPR was the issue.
- DTC P1296 Injector Circuit High to Low Current Transition Time Bank 2
- DTC P0101 Mass Air Flow (MAF) Sensor Performance
- DTC P0405 Exhaust Gas Recirculation (EGR) Position Sensor Circuit Low Voltage
- DTC P1404 Exhaust Gas Recirculation (EGR) Closed Position Performance
- DTC P1621 Control Long Term Memory Performance
The P0101, P0405, P1404 will all set when the EGR is not functioning correctly. It could also cause the vehicle to stall if its stuck open. Fix the EGR issue and see if the MAF code comes back.
The P1296 code indicates an issue with the FICM or the wiring going to it. The Diagnostic chart basically says it's an internal fault and to replace the FICM module.
The P1621 Could be an internal ECU fault but it could have something to do with how you are cycling the key and clearing the codes. I would look at your other issues first before condemning the ECU.
The other P060 is not a full code. The missing digit could indicate an ECU fault as well but we really need the correct code.
Here is the flow chart for the 1296 code.
DTC P0611, P1293, P1294, P1295, P1296, P1658, or P1687
Circuit Description
This diagnostic applies to internal microprocessor integrity conditions within the fuel injection control module (FICM).DTC Descriptor
This diagnostic procedure supports the following DTCs:- DTC P0611 Fuel Injector Control Module Performance
- DTC P1293 Injector Circuit Low to High Current Transition Time Bank 1
- DTC P1294 Injector Circuit Low to High Current Transition Time Bank 2
- DTC P1295 Injector Circuit High to Low Current Transition Time Bank 1
- DTC P1296 Injector Circuit High to Low Current Transition Time Bank 2
- DTC P1658 Fuel Injector Control Module Driver Performance
- DTC P1687 Fuel Injector Control Module Driver Stuck On
Conditions For Running The DTC
- The ignition must be on for DTC P0611, P1293, P1294, P1295, P1296, P1658, P1687 to run.
- DTC P0611, P1293, P1294, P1295, P1296, P1658, P1687 runs continuously once the above conditions are met.
Conditions for Setting the DTC
These codes will set when there is an internal failure in the FICM for less than 1 second.Action Taken When DTC P1293, P1294, P1295, P1296, P1658, or P1687 Sets
- The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
- The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.
Action Taken When the DTC P0611 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.
Step | Action | Yes | No |
|---|---|---|---|
1 | Did you perform the Diagnostic System Check – Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
2 | Replace the fuel injection control module (FICM). Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | Go to Step 3 | — |
3 |
| Go to Step 1 | ` Go to Step 4 |
4 | 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 |
