460 Auto Speedo Pickup

[doingitsideways]

Hello peeps

So, I'm going away next week in the 460 Turbo, nice 300 mile drive a chance to stretch the old girl's legs, let the Robou ECU do it's thing and get the boost needle well into the red when I get into the sticks!

Trouble is, my speedo has pretty much called it a day.

I've had one or two problems with it before, usually after driving through a big assed puddle or something and presumably getting the pickup wet, but it would sort itself out after a few days and suddenly start working again.

I changed the thermostat a couple of weeks ago and it's not worked properly since.
It'll work for about a mile or so from cold, then just drop to zero.

So, has anyone had a similar problem with the speedo pickup?
Also, where is the bloody thing??

Thinking that if I can get to it easy enough, I may be able to clean it up and dry it out?

Just don't really fancy driving about 1000 miles over a week with no speedo and boost under my right foot!

Cheers,

Steve

[Lao]

Hi Steve,

In thinking that the engine system is more or less the same as the 480.

if that is the case, look for a jacket on the gearbox under the airfilterbox, if water reach this jacket, you could see this problem. contact spray will help. (afther drying)

Other option, check the cable, mine has been robing along a piece of metal and was blank, making contact with the metal. little of new tape will help in this case.

I'm no car expert, so let's hope this info can help you.

[doingitsideways]

Thanks for your reply.

Yes, the running gear is identical to the 480 Turbo.

Ok, I'll have a look tomorrow.

What do you mean by "jacket?"

I know the sensor bolts into the rear of the gearbox casing on the manual, above where the R/H driveshaft enters the gearbox.
I presumed it may be different on the auto.

Thanks,

Steve

[Lao]

I'm sorry,

Jacket,... google translate say's plug

"I know the sensor bolts into the rear of the gearbox casing on the manual, above where the R/H driveshaft enters the gearbox."
Yes, that sounds like it, giving it some spray from time to time will help.


Good luck.

[doingitsideways]

Ah, Google translate fail!

In English, a jacket is something one may wear if feeling cold.

Would be very surprised to find one of those under my air filter!

Thanks for your help,

Steve

[doingitsideways]

Right, I found it.

Had a poke around, cleaned up the connections and took it for a drive.
Still doing the same, so I guess it's goosed.

Don't suppose anyone has one knocking about??

Cheers,

Steve

[Lao]

Hi Steve,

Is your rpm clock still working?

If that is the case it coud be the sensor is oké, I have to check the big book.
But something tells me that the sensor is giving info for speed and rpm.

Again, if that is the case, there is a weake part in the cable or you gone have to take out you dash unit and check the print plate.

[Lao]

www.volvo-480-europe.org --> downloads --> Volvo 480 Electrical Schemes

Then take a look at page 56.

I know it's for the 480, but it's probably the same for the 460.

[doingitsideways]

Thanks.

Yes, the RPM signal is fine.

It's only been misbehaving really badly since I changed the thermostat and the sensor would have got wet.

Presumably it's soaked through the top of the sensor and killed it

Steve

[Lao]

I don't think it's the sensor, than your RPM clock would be dead as well.

I belief it's just bad luck:
1-you repair something and something else just break down on that same time.
2-By changing the thermostat you just happend to touch the cable and a weak point has become more damage and is not giving the signal through any more.(my prime suspect)

However, you could use a Multi meter to check the sensor itself, you never know.
But it's very rare these breakdown.

I wish you good luck in finding and fixing the problem, and maybe you could let us know what happend.


Leo