Strange tach cluster issue?

[drddan]

Hey all! I am having an issue with my tach clusters on both of my Festy's. I was wondering if any of you have seen this issue.

Sometimes the cluster lights don't come on when the car is started, but come on later while driving. Intermittent problem. Sometimes it does it, other times it doesn't.

The white tach cluster in the red festy was an install to replace the non-tach cluster, and the black GL festy white tach cluster is stock. Both clusters do this.
It seems related to the cold, sometimes. As the car warms up while driving, the cluster lights will suddenly come on!

Sometimes I can make them come on by turning the heater blower switch on and off.

What the heck could be causing this? It is annoying driving at night without being able to see the speedometer!

Thanks in advance!

[rickbz28]

My 600k Festy has had this same problem just as you described.Never figured it out and that car doesnt' get driven much anymore,but would be interested in what the solution is.

[jayber]

check for loose grounds

[Team Lightning]

The Lights on the right side of my 90L non tach cluster started that, when it was cold, at approx 13K miles . They would stay off until the interior warmed up. It did that until I replaced them with LED's 4 yrs ago. Wiring was good so i never found a reason it did that.

[eurotiva]

Mine does it to only when cold. One whack on top of the dash makes them come on

[navdoc101]

Cold weather does strange things to our cars.
My Fuel gauge only works when its cold.

[drddan]

Wow. This is a strange phenomenon. I am thinking it has to be something in the circuitry of the cluster. Everything else on my clusters work when the cluster lights go out.

I have been known to beat about the dash to sometimes get them to work, too! lol Doesn't work every time though.

Sux that both clusters I have do that.

[FB71]

when you say cluster lights, do mean instrument illumination, or the warning lamps? Two very different critters...

If its the illum you're talking about, very well documented problem. I've traced the faults to two locations. The most common is the pin-fit of the connectors on the back of the cluster. The second is a poor splice in the harness.

[zoe60]

Wow FB71, you know your business. I was gonna suggest looking for cold solder joints on the tack cluster. Is the splice in the harness hard to access? Good info.

[old yellow]

My illumination does work but I still can't see my needles at night... sucks this time of year as it gets totally dark at about 4:30 pm

Also if we are on the subject of cluster lights, my brake warning lamp only come on in the start position, NOT when the e-brake is on Car running or not does not matter and it doesn't light if the key is to the "on" position... it has done this on 3 clusters, so I don't think it is the cluster

[bravekozak]

Headlights on. The cluster splice in the wire occurs ahead of the radio splice. If the radio light comes on and stays on, then it's not the cluster splice. All of the instrument panel illumination is grounded through the dimmer switch.
Remove the dimmer switch and install a jumper from red/white to black. If the instrument lights come on full brightness and stay on, then replace the dimmer switch.

[bravekozak]

Please install the jumper with the headlights off.

I think the Ford part number is E8BZ-11691-A

Does anyone know if an Escape switch will fit our dash?
I would change the connector in a heartbeat. No wheel.

[sc72]

drddan, same problem here, they only come on when the cabin warms up, no amount of tapping will make mine come on.

[Team Lightning]

Occasionally mine would come on when you smacked the dash, but usually waited until the cabin warmed up. Only the right side lights over the Temp gauge did this.
Left side never flickered

[FB71]

Headlights on. The cluster splice in the wire occurs ahead of the radio splice. If the radio light comes on and stays on, then it's not the cluster splice. All of the instrument panel illumination is grounded through the dimmer switch.
Remove the dimmer switch and install a jumper from red/white to black. If the instrument lights come on full brightness and stay on, then replace the dimmer switch.

Not 100% accurate. It's a gang splice, and I've found individual conductors can have issues, not necessarily all circuits are affected. The big issue is how the splice was made originally. It's an open barrel crimp, and it's not sealed well. Over the years, corrosion starts to build in the splice, causing an intermittent, and temperature sensitive circuit fault.