RRSTDV8 wrote:

potentiometer

Thats the one  Mike

2014 Facelift Discovery

I had exactly the same symptoms you described. My problem was caused by a faulty brake pedal switch. I used to get a momentary loss of power and "engine system fault" message would be displayed along with an icon of a manual. It's a very common problem.
Good luck.

Thanks.

Usually no message is shown when I get the momentary power loss but sometimes the HDC fault message pops up and if cruise control is engaged at the time "Cruise Cancelled" always pops up (this message not mentioned in the manual ).

Have ordered a new brake light switch on the grounds that they seem to have a limited life and its probably due a change regardless of whether it is causing this problem.

Is Bullet going to update us on his issues? 2008 MY Java Black TDV8 HSE

Paddi wrote:

Thanks.

Usually no message is shown when I get the momentary power loss but sometimes the HDC fault message pops up and if cruise control is engaged at the time "Cruise Cancelled" always pops up (this message not mentioned in the manual ).

Have ordered a new brake light switch on the grounds that they seem to have a limited life and its probably due a change regardless of whether it is causing this problem.

Is Bullet going to update us on his issues?

Installed the new brake light switch and ..........IT'S FIXED. Well let's say it completed a 40 mile dash up and down the M1 without doing it - so fingers crossed.

The old switch was showing signs of arcing internally at the contacts. I'll post up a 'how to' later as I took some pics.

So finally after initially suspecting it was a gearbox fault (that's what it feels like) and spending quite a bit on gearbox service and new battery we have a fault-free RRS. Wonder how long that is going to last?  2008 MY Java Black TDV8 HSE

Can anyone explain why the Brake Light Switch would cause a loss of power and a Engine Fault Message? I experienced these symptoms today.

I was cruising at 70 when I suddenly got a loss of power slowing me down to 50 and the error message System Engine Fault. No warning lights or other warnings. I continued for a short way and the error cleared but still no power. Stopped and switched off, locked the car, unlocked the car and started her up. No error and full power back.

Did a search and came up with this link. 2006 Supercharged

Yes. One of the things that the brake pedal switch does is cut the fuel to the engine; this is intended to improve fuel economy and reduce emissions. The switch has two sets of contacts inside it; so apart from controlling the brake lights it also informs the engine ECU that the brakes are on and the ECU takes appropriate actions or inappropriate ones if the switch is faulty. 2008 MY Java Black TDV8 HSE

Cheers for that. Not sure if this is the problem but it's a cheap fix if it is so have ordered one and I'll change the switch as soon as it arrives. It's cheaper to do this than drive the 30 miles to dealer. 2006 Supercharged

Fitted the switch last week and the error has not reproduced itself, fingers crossed that's it fixed.

Cheers for the help.  2006 Supercharged

Got the error again today. It only happens on the same bit of road each time. Always on a long fairly steep road just south of Inverness. Just cruising around the 70 mph and nearing the top when the loss of power happens with the same Engine System Error happens. Have to stop and turn it off for 30 seconds and then it's fine although it does take the error message about another minute to clear. Still haven't had the error codes read yet. 2006 Supercharged

Paul HH - Strange coincidence & a supercharged. I've just cpoied this off a previous thread I replied on?
I used to run the car then stop somewhere - pull of about an hour later & get exactly what you have. It got worse during the summer - the same spot on the way home from work - I used to boot it up a hill - it turned out to be a thermostat in the coolant hose - £15 & sorted.
Good luck.









Burning Bridges - Gone for Ever More. 16MY Estoril Blue SVR.............
17MY Autobiography Dynamic - Corris Grey - WOW.
14MY Autobiography Dynamic - SDV6 - Fuji White
12MY Autobiography - SDV6 - Santorini Black - Dual View - Rear Entertainment - Sunroof.
12MY Autobiography - SDV6 - Orkney Grey - awesome ;(
2005 Java Black - 4.2 V8 Supercharged First Edition- will never be forgotten ;(

Cheers Peachy, I actually keep getting low coolant error as well, comes and goes. I'll have to have the Therostat looked at. Is it actually in one of the hoses rather than the water pump? 2006 Supercharged

Yes - wasn't there when it was fixed - but it was done on my drive in 5 mins by a neighbour - RAC mechanic - I will ask him tomorrow to show me exactly where it was & maybe add a photo - he said its a common fault & went straight for the thermostat - no problems since ( 2 years now ) - guess what used to get the same message low coolant. 16MY Estoril Blue SVR.............
17MY Autobiography Dynamic - Corris Grey - WOW.
14MY Autobiography Dynamic - SDV6 - Fuji White
12MY Autobiography - SDV6 - Santorini Black - Dual View - Rear Entertainment - Sunroof.
12MY Autobiography - SDV6 - Orkney Grey - awesome ;(
2005 Java Black - 4.2 V8 Supercharged First Edition- will never be forgotten ;(

Peachy, I'd really appreciate that. That'll be excellent if it is the same. 2006 Supercharged

It was definately this part

http://www.brookwell.co.uk/products/RANGE_...ure_Sensor

Sorry if I've broken any advertising rules - just identifying the part. 16MY Estoril Blue SVR.............
17MY Autobiography Dynamic - Corris Grey - WOW.
14MY Autobiography Dynamic - SDV6 - Fuji White
12MY Autobiography - SDV6 - Santorini Black - Dual View - Rear Entertainment - Sunroof.
12MY Autobiography - SDV6 - Orkney Grey - awesome ;(
2005 Java Black - 4.2 V8 Supercharged First Edition- will never be forgotten ;(

I'll get one ordered up and fit on spec, and then keep my fingers crossed again  2006 Supercharged