SKYHOOK U1706 FAULT CODE

[tonycharente]

Hello all,
I have a 4200 CambioCorsa.
I'm getting a U1706 fault code using my newly purchased Launch X431. It's in the "Sachs Skyhook Suspension" module and the full fault reads "U1706 No Communication With NFR2608".
I've cancelled the fault code (so that no fault is shown) but it comes right back. As far as I know my car drives normally, but then I've only ever driven one other 4200, and that only for a short distance. The car has recently passed its "Contrôle Technique" (vehicle inspection like an MOT) with no faults. There are no dashboard warning lights, MIL or otherwise - had I not bought the Launch I would still have been been blissfully ignorant.
Any ideas please? Should I be worried?
Cheers
Tony

 

[spkennyuk]

Hello all,
I have a 4200 CambioCorsa.
I'm getting a U1706 fault code using my newly purchased Launch X431. It's in the "Sachs Skyhook Suspension" module and the full fault reads "U1706 No Communication With NFR2608".
I've cancelled the fault code (so that no fault is shown) but it comes right back. As far as I know my car drives normally, but then I've only ever driven one other 4200, and that only for a short distance. The car has recently passed its "Contrôle Technique" (vehicle inspection like an MOT) with no faults. There are no dashboard warning lights, MIL or otherwise - had I not bought the Launch I would still have been been blissfully ignorant.
Any ideas please? Should I be worried?
Cheers
Tony

Hi Tony. I think its a quirk of the launch system. The code relates to loss of power to the suspension module at key on / start position.

When you start your car power is briefly cut to everything ie radio goes off light dim etc. The launch is detecting that and registers a fault.

Basically if you clear it with the engine running i think it will stay off. Once you restart the car it would then show in the launch again.

If there was an actual fault on the suspenion it should give you a code that relates to a specific shocker.

I cant tell you 100% but i believe thats what happens and its just a quirk of launch software and not a genuine error.

Phil or conaero may be able to confirm as they both have launch as well.

 

[philw696]

Here in France the car is subject to a thorough shaking to test the shock absorbers during the CT telling the tester how good the shocks are.
When I was last testing in the UK we had a shaker on the left front corner of the 4 post MOT lift made it easy to detect ball joint ware.
I would second @spkennyuk that it's a quirk of the Launch.
As I don't have anything Italian at the moment I haven't been able to diagnose in those fields but it's been brilliant in everything I have worked on.

 

[tonycharente]

Thank you both very much for your answsers.

Yes, the French MOT involves putting the car on a rolling road to test the brakes but it also shakes the car violently - I always think something is bound to fall off! I'd assumed it was the same test Europe wide (for now...) but apparently not. It's been nearly twenty years since I last put a car through an MOT in the UK.

VERY reassured concerning the "quirk of the Launch system" explanation. I've just tested the theory (clearing the U1706 code with the engine running and then going for a drive without restarting the car) and it hasn't come back. Excellent news,thank you.

Thank you so much, both of you !!!
Tony

 

[voicey]

It's not a quirk of the Launch. When you do a global scan with any diagnostic tool, all modules are connected to and read for errors. When the NFR (ABS) module is communicating with a diagnostic tool it disconnects from the CAN. Other modules that are expecting to talk to the NFR register an error when they can't see it.

 

[tonycharente]

It's not a quirk of the Launch. When you do a global scan with any diagnostic tool, all modules are connected to and read for errors. When the NFR (ABS) module is communicating with a diagnostic tool it disconnects from the CAN. Other modules that are expecting to talk to the NFR register an error when they can't see it.

Many thanks Voicey - so if I understand it correctly, it's not just a Launch that would do it, and I still have nothing to worry about?