U0307

Code

Generic U — Network/User

Software Incompatibility With Glow Plug Control Module 1

Brand: Generic

Type: U — Network/User

Views: UK: 21 EN: 33 RU: 24

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Glow Plug Control Module 1 has incorrect or mismatched software/calibration
Incomplete or failed module reflash or software update
Replacement module not programmed to vehicle (wrong part or VIN calibrations)
Corrupted module memory or internal fault after update
CAN/bus communication errors causing corrupted software ID transmission
Battery/voltage issues during programming

Symptoms

Permanent or intermittent Glow Plug/Preheat warning lamp
Difficult cold starting or extended crank time
Reduced cold‑start performance or limp functionality in cold conditions
Diagnostic trouble codes stored for glow plug module and possibly other modules
Possible communication warnings or CAN bus related codes present

What to check

Connect OEM-level scan tool and read all U and P codes; note freeze frame and history
Record software part number (SW), calibration ID, and hardware ID from Glow Plug Control Module 1 and from related modules (PCM/ECM)
Check service bulletins and parts database for required software level or reflash instructions
Verify VIN and configuration data programmed in the glow plug module
Inspect module connectors and wiring for corrosion, damage, or poor contact
Check battery voltage and charging system during attempted programming (must be within spec)

Signal parameters

Glow Plug Module software part number and calibration ID (SW/CAL IDs)
Module response time to diagnostic requests (timeout or no reply)
CAN bus error count / CRC errors
Battery voltage during programming
Glow plug diagnostic status messages (if available) and their timestamps

Diagnostic algorithm

Retrieve and record all stored codes and freeze frame data from all modules; do not clear codes yet.
Verify the vehicle VIN, part numbers and expected software/calibration level for Glow Plug Control Module 1 using OEM resources.
Read the glow plug module SW/CAL and compare to the expected values; check other modules for matching network software levels where required.
Inspect wiring and connectors at the glow plug control module for corrosion, bent pins, or water intrusion; repair as needed.
Verify stable battery voltage and charging system before attempting any reprogramming (follow OEM voltage limits).
Attempt an OEM reflash/upgrade using the correct software package and programming procedure for this module and vehicle VIN. Follow security and J2534/tech tool steps exactly.
If reflash succeeds, clear codes and perform a road/cold-start test to confirm normal operation; re-scan for stored codes.
If reflash fails or module does not accept programming, confirm firmware/hardware compatibility; consider recovering with dealer-level tools or replacing the module with correct, programmed unit.
After replacement or successful reflash, verify all related modules have compatible software and perform final diagnostic verification and code clear.

Likely causes

Module was replaced but not correctly programmed to the vehicle
Previous software update failed or was interrupted
Wrong software/calibration loaded (dealer or workshop selected incorrect file)
Module has internal memory corruption and will not accept correct software

Fault status

⚠️ Status

Software incompatibility detected for Glow Plug Control Module 1. Module software/calibration does not match expected vehicle configuration or is corrupted. Reprogramming or correct module programming required; check vehicle-specific update procedures.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 1.0-3.0 hours