Problems With Dashboard

[jez9999]

My car is a 7 year old Corolla GS diesel. Every now and then I have weird problems with the dashboard; 2, in fact.

The first is that, on quite a regular basis, the speedometer will just drop to zero. Often, at the same time, the orange 'engine' symbol on the dashboard will light up, which the owner's manual helpfully tells you means 'take back to dealer'. Thing is, often after a while the speedo will come back up and work again, and almost always when I turn the engine off and on that orange light disappears and the speedo works again. I did actually take the car to the dealer about this, but they seemed pretty clueless and very expensive. They said it could be a problem with the dashboard component OR some component in the gearbox, and to fix both would be about £500 in parts alone. I told them not to do the work, and was hoping you guys might have slightly more of a clue. ;)

The second is a more minor problem; of late, the fuel level needle has started waving around way more than usual. Especially when I'm on low fuel, the thing can go from half-full to completely-empty, based on whether I'm braking or accelerating. Surely it shouldn't do that? Is there some component in the fuel tank that can come loose or something and cause this? Could it be an electrical problem?

[Twincam.GTi]

So sometimes your 'Mil/check' light is coming on - and then going out ...I say the cars trying to throw up a fault code.

You car is pre EOBD2 compliant ? so you can still read/clear the codes manually (if there are any!).

These two items I would say are connected.

as the car is still drivable I would like to suggest this first:

Disconnect you Battery for over 30 seconds, then reconnect as normal and see if this makes a difference (not saying it will). Please remember to find/take note (if required) of your radio code also your time clock (in the roof usually) will need reseting and your alarm (if fitted) sometimes will go off as you reconect Battery - so get ready to jump out of your skin :D !

If fault returns next week/continue then I have other suggestions

[mollycorolla]

i just bought the boyfriends 98 corolla and it has the same problem with the fuel gauge. it seems to have a mind of its own. doubt mine is as sensitive as yours by the sounds of it but yea mine tends to go up and down a good bit too depending on what im doing. none of my last cars done it so it cant be my driving. i cant help but i just thought id throw it in to let you know you're not alone!!!

[jez9999]

So sometimes your 'Mil/check' light is coming on - and then going out ...I say the cars trying to throw up a fault code.

Ah, yes... the 'Malfunction Indicator Lamp (MIL) (Check Engine Light)'. Yeah that seems to be the symbol that comes on.

You car is pre EOBD2 compliant ? so you can still read/clear the codes manually (if there are any!).

It's an X reg (2000), so probably? How do I read/clear the codes manually?

These two items I would say are connected.

as the car is still drivable I would like to suggest this first:

Disconnect you battery for over 30 seconds, then reconnect as normal and see if this makes a difference (not saying it will). Please remember to find/take note (if required) of your radio code also your time clock (in the roof usually) will need reseting and your alarm (if fitted) sometimes will go off as you reconect battery - so get ready to jump out of your skin :D !

If fault returns next week/continue then I have other suggestions

OK I will try doing that but I don't see how it will help. :-)

[jez9999]

Hi,

Tried doing the Battery thing but it's still got the same problems. How can I read the codes manually?