All of a sudden, RRSport HSE 2006 can not speed above 30mph. We've checked all the fuses (is there any specific one to check related to speed?), all ok.

Any idea where to check to resolve this issue?

Thanks,

Femi

Are there any warning lights illuminated or messages displayed?

Also, it's isn't in lo-range by any chance, is it?

are you towing a caravan? purple people eater

There are no good days, just some days that are not as bad as others!


Gone RR 4.0 P38 Autobiography MY99 Red ( money pit)
Gone RRS MY06 2.7TDV6 HSE Rimini Red
Gone RRS MY10 3.0TDV6 HSE Bali Blue with lots of bits (never grew to love it)
Here Now - 3.6 TDV8 FFRR OVERFINCH Stornoway Grey - loving it x
My work car Ford Mondeo 2.0 TDci Zetec auto Estate in Silver

There is no warning lights illuminated or messages displayed. But when I did a "QUICK TEST (FULL VEHICLE FAULT READ)" on Autologic Diagnostic tool, I found a new fault (not sure they were there before or after the speed limit issue) as below:
HVAC FAULTS
Note:
B1B74-00: Front foot-defrost mode stepper actuator
B1B75-00: Front foot-face mode stepper actuator
B1B76-00: Front left air blend stepper actuator
B1B77-00: Front right air blend stepper actuator
Also whenever I did a Transfer Case (TCM) Calibration using the Autologic Diagnostic, a new TCM fault message comes up as below:

P0806-00: Clutch Position Sensor - Circuit Range/Perfomance -- this disappears whenever I did "clear faullts"
. no sub type information

Its not in low-range and I'm not towing any object.

Ignore the HVAC fault codes, most RRS's and D3's have these. I don't get the clutch fault code though, I would have thought that would apply to a car with a MANUAL gearbox. Does the gearbox stay only in a low gear? ie does not change up through the gears as it should. RRS TDV8 Buck Blue (no, not now in my dreams). ..........D3 TDclankety clankV6 ............BMW 318i

It stay on 4th gear when it reach 30mph.

P0806-00 Description
Mismatch of actual and expected/calculated actuator position Internal differential actuator error
Possible action:
Calibrate the clutch and range change mechanism using the approved diagnostic system or by the procedure listed in the description and operation. Refer to the relevant section of the workshop manual. Clear the DTC and retest. If the problem persists, renew the differential actuator

For the calibration you may need the dealer IDS as I am not sure if teh Autologic has this feature.

Hope this helps. RRS SDV6 HEV Dynamic
XKR 700 BHP with Twin-screw and LSD

Avos, thanks for the info. You mentioned "or by the procedure listed in the description and operation. Refer to the relevant section of the workshop manual. ". Where can I find this procedure?

Not sure if you have access to an IDS, but If so, the new SDD (Symptom Driven Diagnostics) software on the IDS may lead you to the menu option either via the DTC or via selection of the area you want to investigate (rear axle/diff). However this SDD is relatively new, and may not work flawlessly yet.

I have no knowledge of the autologic unit, so am not sure if that is capable of performing this routine. RRS SDV6 HEV Dynamic
XKR 700 BHP with Twin-screw and LSD