Speedometer Dead

[scot850]

There are videos on it, the hardest part is getting the case open.

Neil.

[MrAl]

There are videos on it, the hardest part is getting the case open.

Neil.

Hello Neil,

Oh really? Well for me that would be sort of easy because i have taken plastic cases apart many times using the Dremel. I made up a special cutter for plastic. It's a very very thin blade like a saw blade with no teeth. It melts its way through and so doesn't actually eat up any plastic like a regular saw blade would. That allows the case to go back together with nearly the exact fit as it was. Just cant cut too deep.
I've done many a wall wart, electric can opener, you name it. Only takes about 1/2 hour if you are careful.
The hard part for me would be taking those bolts out underneath with the worry that something could go wrong.


Ok, so i tried the cardboard wedgie trick, and unfortunately, no luck. Well, that's unless you didnt really want to fix the speedometer so cheaply. If you did want to fix the speedometer, then it DID work (ha ha).

YEAH, i can't believe it actually worked!!
After i did the cardboard, i got in the car and drove away but forgot to check the speedometer because i was so intent on checking the GPS speedometer i got recently, which works pretty nice BTW. Then about halfway to the dollar store i looked to the left a little and saw that the speedometer read about 20 mph or so. I was floored! Truely amazed that it worked so well. I checked with the GPS speedometer, and they were close within maybe 1mph or so. Now i guess i have to figure out a more permanent solution because the cardboard will probably get weaker due to the moisture from being outside all the time. Maybe plastic like the link had shown.

So thanks much for reminding me about that link somehow i overlooked it. I think i half believed it would work too because it seemed so simple. Apparently a lot of people got this to work though with this car so i guess it's a big issue. Apparently the connector PC board pads are not large enough to hold enough solder to keep the pin solder from cracking after 25 years. Maybe there is more than the usual stress on the connector also.

I really have to thank you for this one Neil i don't know how i could repay you for this help. Maybe something will come up i will be able to assist you with in the future.

[scot850]

Hey as they say, " Even a broken clock is right twice a day............!"

Neil.

[wizechatmgr]

a single ABS sensor failure can take out the speedometer on a V70 at least.

Grunhilde the 1998 has the left front sensor inop and no speedo

Oh thanks Steve that was one of my major questions.
Now to figure out which one.
The Obd2 speedometer signal is dead too.

The speedo sensor signal all comes from the ABS module. I believe it picks it up using the front left wheel sensor as @Abscate previously stated. Even if all 3 other sensors work, you lose this sensor signal and you're screwed as far as the speedo is concerned.

If you have a bad ABS connector at the speed sensor, soldering this is nearly impossible unless you're really good at solder and have plenty of flux on hand. Frankly, as much as I hate crimp connectors, a weather proof crimp might be better for this particular application.

[scot850]

The issue is not the sensor, the issue is broken contacts in the ABS module. The cardboard wedge between the connector and the ABS pumps/module body pushes the broken connectors closer together and can get enough pressure on it for a short term fix. The only real fix is to re-solder the contacts in the module.

Neil.

[abscate]

The real fix is sending your unit into mattymoo and getting back a known, tested working sealed unit for $100

[scot850]

Need to check the pricing. It is a bit more than $100 these days. For a 98 it is $160-170 US

Neil.

[MrAl]

a single ABS sensor failure can take out the speedometer on a V70 at least.

Grunhilde the 1998 has the left front sensor inop and no speedo

Oh thanks Steve that was one of my major questions.
Now to figure out which one.
The Obd2 speedometer signal is dead too.

The speedo sensor signal all comes from the ABS module. I believe it picks it up using the front left wheel sensor as @Abscate previously stated. Even if all 3 other sensors work, you lose this sensor signal and you're screwed as far as the speedo is concerned.

If you have a bad ABS connector at the speed sensor, soldering this is nearly impossible unless you're really good at solder and have plenty of flux on hand. Frankly, as much as I hate crimp connectors, a weather proof crimp might be better for this particular application.

Hi,

I've been soldering since i was around 10 years old. I've soldered AWG32 to AWG4 and some things most people don't solder, like a car radiator (2 actually) and they didn't leak after that. I've used irons and guns from about 20 watts to about 500 watts. The big ones for the large terminals and wire. Even soldered stainless steel straps that go around transformers to hold the two sides together.
You name it, i probably soldered it (ha ha).

My real problem is taking things apart on this car. everything i go to fix requires a touchy and big job like the alternator and now the ABS module. I could solder the ABS contacts in a heartbeat such that they last 50 years, but if i can't get the dang thing off the car i can't do anything like that.

Yes thanks about the front left wheel sensor, i'll try to keep that in mind.

[MrAl]

The real fix is sending your unit into mattymoo and getting back a known, tested working sealed unit for $100

Hi Steve,

Yes that sounds like a good solution. I may have to pay someone to take the ABS module off for me, and i could most likely get it back on myself.

Thanks.

[MrAl]

Need to check the pricing. It is a bit more than $100 these days. For a 98 it is $160-170 US

Neil.

Hi Neil,

Yes the only thing that goes down these days is my bank account balance (ha ha).

$100 would be very reasonable, $150 getting up there.
And yes i forgot you have to take the box apart too if you do it yourself, then seal it back up. Probably better to send it out like Steve suggests.