1987 Ford F150 old fuse box has different gauge wires sharing the same fuse post. Can these wires just be connected together and run to a fuse? Original fuse box was taken out of the truck.

 

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A fuse box diagram on Utube shows the PCM fuse is #5 (brown) on the left side of the fuse box.
I checked the fuse and found it was good. I changed the fuse anyway just as a precaution.
There are eight (8) wires of various colors to the PCM connector.
I have a FIXD analyzer. When plugged in; it shows no power at the connector.
When I plug the analyzer into the PCM port on the wife's car (Toyota Sienna), the analyzer lights up even when the key is off.
Since I have no wiring diagram (yet), I don't know which one is the power wire. I can't see the outgoing wire colors at the fuse box.
The fuse box is in the very tight area, and I'm not able to do a continuity check between the stated fuse (#5) and each wire on the PCM connector.
Anybody have a wiring diagram of the PCM circuit?
Thanks,
Tom

 

Yup, fuse #41 (20 amp) was blown.
Related fuses #37 and #39 were good.
It appears that blown fuses are a known issue.
I'm not a smoker and don't use the cigarette lighter.
Maybe there are too many "devices" being monitored on that circuit.
If fuse #41 was in a more "user friendly" location, I would get an amperage reading during operation.
If it blows again, I will probably increase it to a 25 amp.
Thanks for the feedback, much appreciated.