Hello; new guy with a question for some of the electricians: This is the back side of the temp gauge and ammeter. Could someone explain the printed circuits right above the warning lights? It looks like several circuits end there but don't connect to each other. I'm trying to modify the panel and relocate the lights. Thank you. Rick A #ad

 

the printed circuit is generic to multiple vehicles.
those circuits may not be used on your cluster, but will be used on others.

 

1987/88 F150/350 & Bronco:

E8TZ-10K843-C .. Printed Circuit Board-Use without Tachometer / Marked: E7TF-10K843-AA or E8TF-10C956-AA / Obsolete

E8TZ-10K843-B .. Printed Circuit Board-Use with Tachometer / Marked: E7TF-10K843-BA or E8TF-10C956-BA / Obsolete

 

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Thank you for your responses. The truck is an F-250 but I don't know the model; I've got most everything stripped off of it.
Here's a better pic. You'll notice that just above the left warning light socket there are five circuits that just end and aren't connected to anything. According to the wiring diagram they should complete circuits to a couple of the lights. I don't understand how the circuits get completed. Hoping someone can explain it.

Thanks again,
Rick A

 

they are connected to the light power strips below them. you just can't see the connection due to the dust and old age buildup.

 

The light socket has the other half that contacts the printed circuit.

 

As I understand it, (and I'm not an electrician nor ever played one on TV!) the far left circuit is the ground return for the temp light and instrument lights, next is the oil pressure warning circuit, next is from the temp sensor and gauge, the next comes up from the temp warn light, and the far right comes down from the temp gauge. All that makes sense but what loses me is the circuits just end near each other- they don't connect. That's what I'm hoping someone can explain.

As I mentioned, I'm modifying this truck considerably ( base for a WWII vintage truck replica) and want to relocate the lights. I don't want to wire it wrong and fry a gauge or sending unit.

Thanks,
Rick A

 

The circuit print just stops at the light socket
Look at the bottom of the twist part where the bulb presses in
It has 2 contacts that come from the sides of the bulb, and go the the bottom of the assembly
When you put it in the slot, and twist, it makes the contacts in the bulb holder contact the strips in the printed circuit

I'm guessing that is the answer to the question.

If you don't have the bulb holders, I have some here, I can take a picture.


Just for your info, there are 2 different types of bulbs in that panel.
One is brighter than the other.

one for illumination, one for warning

 

Let me phrase it another way: the second light from the left in the pic has a circuit going up to the second position from the right in the area we're discussing and ending there. The other side of the bulb goes to the ground. Since the "wire" from the bulb isn't connect to anything, how does it operate? I think, but not sure, it's the temp warning light.
Rick A
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