1999 Mercury Cougar Speedometer

JONATHANCDEVIN

MEMBER
1999 MERCURY COUGAR
2.5L
6 CYL
MANUAL
171,178 MILES

My speedometer stopped working the other day so I lifted my var up on the hoist and checked my VSS sensor I found that the outer coating of the wires were cracked and the copper wire on all three wires was showing and were also touching each other. I ordered a new VSS sensor and installed it go to test the car out and still no speedometer I used a snap on solus scanner and found that the pcm was reading the VSS but still no speedometer I was wondering is there any sort of circuit protection inside the gauge cluster? Or maybe something fried inside the cluster itself trying to figure this out not sure what is wrong and what steps to tak from here

Thursday, June 11th, 2015 AT 9:50 AM

3 Replies

JDL

MECHANIC
16,098 POSTS

The signal wire from vss has a splice according to our database. One leg goes to instrument cluster, the other leg goes to pcm. It is possible, because of the splice, for the pcm to see that signal and instrument cluster doesn't. At the instrument cluster, the white wire with blue tracer is the signal wire.

Any applicable trouble codes? I think you have better diagnostic tools than I have.

At the moment, I can't rule out a problem with instrument cluster? I don't know if any internal protection?

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Thursday, June 11th, 2015 AT 10:53 AM

JDL

MECHANIC
16,098 POSTS

The splice for s60 for that signal wire just says engine harness, for location. I'd have to follow wire color to find splice.

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Thursday, June 11th, 2015 AT 10:59 AM

JDL

MECHANIC
16,098 POSTS

I forgot to ask, if you have one, does the tach work? If it does and the speedometer doesn't, I'd have to suspect your instrument cluster.

Sorry about all the posts, I can't edit my posts. Have a good day.

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Thursday, June 11th, 2015 AT 11:50 AM