V70: Ecu problems

[BrockyV70Turbo]

Thanks guys, do you think one from a scrapper would be ok , or should I go to a main stealer for one?

[Jod T5]

Originally Posted by brockyV70T

Thanks guys, do you think one from a scrapper would be ok , or should I go to a main stealer for one?

FRF would be my recomendation....

http://www.volvoforums.org.uk/showthread.php?t=57125

Cheers
Jod

[BrockyV70Turbo]

Originally Posted by Jod T5

FRF would be my recomendation....

http://www.volvoforums.org.uk/showthread.php?t=57125

Cheers
Jod

Cheers Jod,

Does this sensor effect fuel economy? If it doesnt then I wont bother replacing it. I need new front discs this month, and am off to Germany this month on holiday.

[Jod T5]

Originally Posted by brockyV70T

Cheers Jod,

Does this sensor effect fuel economy? If it doesnt then I wont bother replacing it. I need new front discs this month, and am off to Germany this month on holiday.

Tbh i would not know exactly what the pressure switch does, technically ,without doing some research, (obviously it a switching device active at a certain pressure) but i dont expect its apparent failure will cause any extra fuel usage

Cheers
Jod

[BrockyV70Turbo]

Thanks Jod,
I was asking because Mr T said it is on the same circuit as the other sensor that I replaced. That other sensor does affect fuel apparently. So I assumed it would affect it somehow. If I could find out what sort of fuel economy I should be getting from the car, that would tell me. I have been doing around 31 mpg on a motorway.
I have found another sensor which seems to have an open circuit inside it. That is just next to the brake servo, so assume it tells you when the brakes need replacing. But thats another story.

Cheers

[Jod T5]

Originally Posted by brockyV70T

Thanks Jod,
I was asking because Mr T said it is on the same circuit as the other sensor that I replaced. That other sensor does affect fuel apparently. So I assumed it would affect it somehow. If I could find out what sort of fuel economy I should be getting from the car, that would tell me. I have been doing around 31 mpg on a motorway.
I have found another sensor which seems to have an open circuit inside it. That is just next to the brake servo, so assume it tells you when the brakes need replacing. But thats another story.

Cheers

As i mentioned i have no idea what the switch function actually is and it seems strange it shares a code with a apparently unrelated sensor. The barometric sensor would effect economy, for sure, the A/C switch, probably not, unless it caused the A/C to run against the wishes of the driver...
But as i say without reference this if off the top of my head
Cheers
jod

[dooby]

Hiya,

maybe I got the wrong end of the stick but I thought the point was both these 2 sensors/switches share a common earth, so although a failing A/C pressure switch wouldn't normally cause fuel issues, if the voltage is being messed up by it, it could cause the barometric pressure sensor to look like it's reading high or low to the ECU, hence bad fuel consumption?

I wonder if you could just disconnect the A/C switch if you're prepared to clear the fault codes when you replace it, and live without its demisting abilities for the Germany trip? That assumes it's the A/C switch causing a bad signal, rather than the wiring to it...

Cheers, Pete

[BrockyV70Turbo]

Originally Posted by dooby

Hiya,

maybe I got the wrong end of the stick but I thought the point was both these 2 sensors/switches share a common earth, so although a failing A/C pressure switch wouldn't normally cause fuel issues, if the voltage is being messed up by it, it could cause the barometric pressure sensor to look like it's reading high or low to the ECU, hence bad fuel consumption?

I wonder if you could just disconnect the A/C switch if you're prepared to clear the fault codes when you replace it, and live without its demisting abilities for the Germany trip? That assumes it's the A/C switch causing a bad signal, rather than the wiring to it...

Cheers, Pete

Hi Pete. I aint sure exactly whether it is causing the old girl to sup too much juice, I just presume it is. And what you wrote there makes sense to me: re voltage messed up etc !!!
It turns out there are two sensors on the AC system ( HP AND LP sides). So I have ordered both sensors, as I know one to be deffo defect. I have tried disconnecting the AC but the fault re-apears after a few miles. I went onto 247 spares.com and found the parts in Doncaster ( both with 90 day warranty). When they get here on Monday, I will swap em over and see what happens.

[BrockyV70Turbo]

THANKYOU, THANKYOU, THANKYOU for everyones help with the fault on my car. I replaced the AC linear sensor this evening. I reconnected the battery and the light stayed off. I went for a drive- went past the 2.6 miles it normally stays off for, got to 5 got to 6 , drove 10 miles and the light stayed off. And it even seems like I am getting a bit more poke from the engine. And to cap it all the AC now works properly...........Once again thanks guys. Especially Mr T. who came up with the solution.

Great site this innit !!!