A Question That May Stump Even The Best Techs

July 28, 2004

First off I own a maxima and I love it but this is my fiance and our other car.

We own a 98 Camry LE. How many miles ? Somewhere around 85-95k?

About 2 years ago we noticed our odometer would flicker when ever we hit a speed bump or a pot hole. It would flash to 0 and the next pot hole the miles would come back.

Well after taking it 2 places including the largest dealership in town we found out the car would need a new part behind the glove box and to reprogram the odmoter and to install the part it would be 500US..

Now the only reason why we never had the part replaced or reprogrammed is because the techs had never seen anything like this before and werent sure if they were giving us a right diagnosis.

I thought it was weird that the odometer would flash or blink when it hit a speed bump which makes me thing either something is loose or its something in between thats fried and thats not permitting the signal to go through.

Any ideas or postive help would be appreciated.

Thanks

Proph

July 28, 2004

A few ideas (for what they're worth):

Most modern cars have a dash instrument unit that is normally only

connected to the rest of the car by a few ribbon cables.

The obvious thing to do what be to remove the unit from the dashboard

switch the ignition one notch, then shake the instrument unit to see

if the problem occurs again, if it doesn't it would point to a lose connection

outside the instrument unit, if it does, then it would be something within the instrument unit (probably a replacement needed with reprograming in that case).

Anyway it sounds like a dealer only job, as it will need reprogramming.

But if whatever they do doesn't solve the problem, I presume you don't pay them?

I guess there also maybe a sender unit on the transmission, did they wiggle this to see if it caused the problem?

- S. (I have had much "fun" chasing electrical problems on a variety of vehicles!)

<_<

July 28, 2004

If it resets to zero, then returns to the correct reading after it has hit another bump, then it's a connection/circuitry problem.

I'm instantly suspicious of the dealer saying it needs reprogramming, as bouncing over a pothole cures the fault. I suspect that they have priced a lot of leeway into the quote.

Rich

July 28, 2004

I didnt relay this in the first post but the odometer finally got stuck on 0. Also we had some techs go thru the whole dash panel and couldnt find a thing wrong up there.

So you guys think its something to do with the controls under the transmission?

Thanks

Proph

July 29, 2004

If they are convinced the instrument unit is OK, then they must look to the devices sending data to the unit.

I guess the "Chip" which stores and receives this sort of data, could be outside the

unit (to prevent tampering) ...

They should be adopting a systematic approach, check the sensors on the transmission that send the data, if they are Ok, check the device/chip which logs the the data, then check the display on the instrument unit. Also check all the wiring in between.

The fact that it is stuck on "0" suggests that whatever was loose, may have disconnected completely.

A Toyota dealer should be able to get wiring plans from their head office.

If they are correct and the part mentioned needs replacing at 500USD, then

the only options are to try and get the same part cheaper (junkyard?) and persuade them to reprogram it (umm..?). If they don't succeed then you should need to pay until they have repaired it.

You could try persuading them to open up the "Part" behind the glovebox and checking the circuitary for breaks if possible (if this part has failed).

Many dealers shy away from resoldering circuit boards, prefering you to pay out for a new part. That assumes that it is possible to do this. Any friends into amateur electronics might be able to help as well.

:bookworm: