I have searched for threads similar to this issue and found nothing. I need help ASAP.

93 F150 2wd, 300 L6, 5 speed, 85k... Today, immediately after swapping my cluster out for a "tach cluster" out of a 95 this began. This is most likely a coincidence but never rule anything out until certain. However, now the red battery light does not illuminate when key is on during "prove-out". It worked on the old cluster.

This truck has had (in order) battery and terminals, all wires checked and connections cleaned, starter and alternator replaced within the last two months. Today I noticed the volt gauge was low and lights dimming. Battery (eo) 12.09v, alternator (er) 11.89v at the battery terminals (even upon revving). The battery tested strong at two occasions this evening at properly equipped locations. Alternator was removed, bench tested strong and replaced anyway under warranty. The new one tested strong also. No charge still exists. I checked the loop wire continuity from the "fire plug" to the regulator plug and wiggled (in case of broken wire) and tested solid. Also tested continuity from "hot wire" on fire plug to battery, solid. (koeo) energizer wire tested good as did all other possible grounds and connections. No visible fuse links blown or ANY other fuses or noticeable broken wires.

I need this truck 110% ASAP and have nowhere to turn for this issue. If anyone has had this issue before please inform me of your fix. I appreciate all pointers and leads.

 

I just found a thread on another forum simply by typing my year in front of my search title. The first thing that came up was an issue with the instrument cluster screwing up the charging system. Apparently when you install a 94-96 instrument cluster in a 92-93 there is something different in the circuit film on the back of the cluster that causes this particular charging problem. (hence my little red battery light not working). So now the only problem I have is shaking the $40 back out of the guy I bought the cluster from and purchasing the correct vintage. Thanks people and sorry for answering my own question. Now you all know this gremlin's face well.

 

I put just a 95's Tach in my 1992 because my stock tach wasnt reading right. No problems with that, or charging or anything. Maybe its just the Voltage guage itself.

 

Replacing individual gauges will work, but due to the pcb being different probably screwed the circuits up.

 

The only changes made to the 94-96 clusters was the circuit film on the back and the volt gauge has four prongs. That is my problem. Put the old one back in, works fine. I wish I could just switch out the tach but my old one isn't equipped with a tach. But you learn something new everyday and sometimes it sucks.