Speedo stoppo

[mgm6397]

Hello I have a 2000 Grand Marquis LS with the analog speedometer it has stopped working the odometer does not operate either I replaced the speed sensor on the transmission & still the speedometer and odometer do not work if anybody has any ideas I would appreciate it thankyou

[Kodachrome Wolf]

I would check fuses that power the instrument cluster. If those check out, I'd pull the cluster and check to see if there is power at the plugs and see if the circuit is properly grounded.

By the way, do all your other gauges work?

[mgm6397]

Yes all gauges
work

[sly]

if your cruise control works, it's the connection to the cluster or the speedometer/odometer itself. I have a good speedo/odo from a 99 if needed (probably lists different mileage, but that's not really a matter at this point). Sometimes just unplugging and replugging the cluster connectors will fix the problem.

If the cruise doesn't work, check the connector to the VSS and make sure it's fully seated and not just barely touching.

If that's all good, check the C102 connector by the brake booster under the hood. Again, unplugging it and replugging it usually fixes continuity issues (check the connectors you can get too easiest first of course and work your way up to the harder to get to ones).

wiring diagram of the important stuff from the VSS to the speedo


connector diagram so you can figure out which of those connectors needs reseated


location diagram (c102 is in the top right of this pic)

[mgm6397]

Thank you gadget

[mgm6397]

So is the speedometer odometer separate unit that comes out of the cluster or is it a all one cluster that I have to replace

[sly]

the speedometer/odometer is one unit and will come out of the cluster. It is much easier to replace the whole cluster at once though since you're not having to dissect the cluster, but it's not that hard. just more screws to remove the clear lens, then more screws to remove the speedometer. Then reverse the process to get it all back in.

[mgm6397]

What do u want for your 99?

[sly]

If you just want the speedo section... $40 shipped. If you want the whole thing... $70. I hacked up the circuit on the back trying to do something with my 93, but put it back together. It should work fine as is. You can swap the circuit over from yours no problem since they're the same 99-01 or 02. Be sure to make sure that's the problem first. Don't buy the part off of me expecting that to solve the problem if you're not getting signal to yours. If the signal isn't making it to your cluster, my cluster won't help.

[mgm6397]

But my cruise control works so I'm getting a signal I still have to check c102 first thanks

[mgm6397]

Also how does the whole cluster come out and when out can I check signal to the connector by measuring voltage? Thanks

[sly]

you can, but it won't tell you anything. you would have to put the rear wheels up in the air so you could put it in drive and then you would see a small AC voltage. If you have a frequency setting (Hz) you could see the frequency of the signal go up as you speed up and slow down. Since you have working cruise, the signal is good from the VSS to the PCM... so it might be C102, the connector to the cluster or the speedo itself.

as for getting the cluster out... that requires removing the dash bezel and some trim to get to that. I'll see if my manuals have all that info.

[sly]

also, apparently the speedo is powered from fuse 8 in the battery junction box (fuse box under the hood by the battery). should be a 30A fuse. If that fuse is ok and the C102 connector reseating doesn't solve the problem... time to check the circuits and stuff leading to the speedo.

Here's all the PDFs you'll need to read through to find out how to do that...
Speedo diagnostic procedure
http://www.grandmarq.net/sly/2000%20...0procedure.pdf
Trim removal
http://www.grandmarq.net/sly/2000%20...sh%20Panel.pdf
Cluster removal
http://www.grandmarq.net/sly/2000%20...%20Removal.pdf
Also, if you don't have a copy of your owners manual...
Here's a PDF from Ford: http://www.fordservicecontent.com/Fo.../00grnog1e.pdf

[mgm6397]

Thank you gadget

[sly]

FYI... I'm not gadget