electrical issues

[derekja]

Hi,

 

I've got a 1995 Legacy L, manual transmission. About a month ago the speedometer quit working. Initially it would work when the car was cold, but then quit when it warmed up. It's throwing a P0500, bad VSS sensor.

 

I was in the midst of a crunch at school and decided to drive without the speedo for a while. I've ordered a new VSS, but a couple of things in the interim make me wonder if it's something else.

 

1) when the car is cold, the parking brake light won't go out. If I let the car warm up, turn it off, then start it again the light always behaves normally

2) the gas gauge is behaving erratically. Sometimes going down by a quarter tank over the course of a few minutes. It usually comes back when I turn the car off and restart.

 

"Check the grounds" seems to be the common response to this kind of problem. Other than the ground on the engine and the negative connection on the battery I'm not sure where to check, though. A search doesn't seem to come up with any comprehensive set of grounds that should be tested on the Legacy and the Chilton's guide and AllDataDIY manuals aren't terribly forthcoming other than showing schematics.

 

If there is a ground problem, am I likely to damage the new VSS by not addressing that before installing?

 

Thanks!

 

--Derek

[OB99W]

The brake light indicates more than whether the parking brake is engaged. A simple thing to check is the brake fluid level, which if low can trigger the warning light.

 

Erratic gas gauge indications on many Subarus is "business as usual", and typically doesn't indicate a general electrical system problem.

 

The speedometer problem, given the VSS code, is likely related to the VSS. Since you have it on order, I'd suggest installing the new one when it arrives.