Possible electrical fault/ EGS gearbox fault

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Possible electrical fault/ EGS gearbox fault

Post by Benscab123 »

Keep getting gearbox fault on dash. It will come on (this stops me being able to select any gears other than N and A1 with paddles)
It’s very random, can come on at any time and stays on for a minute or two then clears itself. Seems to be no pattern to it that I can tell.
The only other recurring fault is P0405 EGR which I’m not sure if related ?
When plugged into diagbox the gearbox fault shows as P1718 gear lever signal fault. No idea if this is really the fault or it’s triggered by something else ?
I’ve sold the car (with known faults) but I’d like to try at least put the gearbox right for the new owner before he picks it up after lockdown.
Any ideas anyone ?

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Re: Possible electrical fault/ EGS gearbox fault

Post by GiveMeABreak »

P1718 relates to a coherence fault with the gear selector signal (Lever). The signal from the gear selector sensor is incoherent (one or more of the switches on the selector faulty).

Downgrade modes:
  • If the vehicle is moving in forward gear, automatic mode is activated and reverse gear cannot be engaged
  • Starting possible provided the gearbox is manually in neutral with presses on the brake pedal
  • Possible to engage the gears via the paddles
  • Crawling deactivated
This will bring a '-' up on the panel and the service light. This can can lead to gear change problems, difficulty in stopping the vehicle and a lack of power.

Suspect Areas:
  • Piloted manual gearbox ECU
  • Sealing of the connectors and harnesses
  • 28-way connector of the piloted manual gearbox ECU
  • 28-way harness of the piloted manual gearbox ECU
  • Gear lever
  • Gearbox ECU
  • Earth cable
  • Earth screw