1. Home
  2. Subaru Cars Forum
  3. Wonky speedometer on 2000 OBW

Wonky speedometer on 2000 OBW

Well, my OBW's speedometer started acting wonky as of today. As I'm moving along, the speedo goes to rest at zero for a few seconds, and then it immediately races back up to show the proper speed for a second before going to rest again. The tach is still working normally, so I can estimate the real speed by looking at that. Also I can check the GPS to see my real speed if necessary.

Not a big deal, just very distracting watching the speedo flop around like that. What are behind speedos these days? Is it a cable and a magnet like the old days, or is it some kind of electronic thing? If it's electronic, is there a fuse or something that I can change?

Yousuf Khan

Reply to
Yousuf Khan
Loading thread data ...

That behavior does seem like an electronic intermittent connection. maybe a bad ground or other connection on a PC board?

I dunno

Carl

Reply to
Carl 1 Lucky Texan

Yeah, that may be because it's all gone now, it's working normally again. That day was a somewhat cold night, which had followed a really heavy snow day. Maybe some moisture freezing up?

Or it could've been just the ghost that inhabits the body of my car? :)

Yousuf Khan

Reply to
YKhan

That problem will be back if not sooner than later. I had to replace the speedo cluster to make that intermittent problem go away in my late 99 Subaru Legacy 30 Ed. It probably not a sending unit problem as I did a full year of chasing various electrical theories of loose wires, shorts, intermittent sending unit bla bla bla. In the end it will problably be the speedo cluster. The good thing is that all you need is a phillips screwdriver and about 30 minutes to repace it.

Reply to
X-Eliminator

This seems to be a typical problem on many Subaru cars. I just bought a '99 Legacy and it has the same problem except for the speedo goes dead for longer periods. I have done a lot of research on the net and I believe the problem has nothing to do with either the speedometer itself or the speed sensor(s). A lot of people spent tons of money replacing these parts sometimes several times with varied success. In many cases the problem would come back in a few years after the whole instrument cluster or speedometer was replaced. I believe the real problem is the bad ground connection (due to a design flaw) of the speedometer as have been pointed out by at least two people:

formatting link
?p=5798464&postcount=26 I am yet to prove that this is indeed the root of the problem in my case, but being an electronics engineer myself I am pretty confident that the problem must be bad ground.

/MM

Reply to
MM

I've had quite a few weird little electrical or electronic problems on this car, that come and go. Sometimes they will not reoccur for several years. I once had a problem with one of the turn signals on one side of the car, but not the other. It fixed itself up, and has never occurred since the first days I owned the car.

The bad grounding seems to be a plausible answer.

Yousuf Khan

Reply to
YKhan

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.