Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Error Code 903 - Incorrect Service Identification When Updating Vehicle Module Software Using SDD (SSM74541)
Reference number: SSM74541
ERROR CODE 903 - INCORRECT SERVICE IDENTIFICATION WHEN UPDATING VEHICLE MODULE SOFTWARE USING SDD
TECHNICAL SERVICE BULLETIN
| LAND ROVER: | Defender/L316; Discovery Sport/L550; LR2/L359; LR3/L319; Range Rover/L322; Range Rover/L405; Range Rover/P38a; Range Rover Evoque/L538; Range Rover Sport/L320; Range Rover Sport/L494 |
| SERVICE CATEGROY: | Diagnostic Software Hardware |
ISSUE
When attempting to update the software on a module using JLR VCI, SDD shows the error message: "Error code 903 - Incorrect Service Identification"
CAUSE
We suspect that the latest update of the JLR-VCI is causing
missing diagnostic messages between the JLR VCI and the vehicles modules.
PERMANENT CORRECTIVE ACTION
This concern has been resolved with the release of SDD version 159.00. The manual patch will no longer be available to download and this SSM will be deleted in 7 days.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.