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No Signal To Gauges


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1986 720 4x4 KC

Not getting signal to gauges. Lights and blower motor also not working. 

The fusible links are gone and the wiring is a mess. Alternator charging at 15 Volts.

Oil Pressure, Voltage, Tach, Fuel, and Temp were all working. Went to work for about 8 months and now I get nothing.

This is a farm truck that climbs mountains on its off days.  Would like gauges to work properly so it does not blow up.

Brand new engine, fully rebuilt transmission/TT, new Weber 38. 

Work is about to be full swing and need this guy to tell me how bad hes sweating. So a simple wiring trick would be great.

Have DMM and dash is out, might be able to figure out pics. Thanks for any help

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Where are the fusible links??? Gone where? Removed and what?


Headlamps are on one of the missing links.

All other lights and the heater are on another link.

Gauges are on a third link through the ignition switch.


 Fusible links are attached to the positive battery cable near the post. What's there now? Got a picture?



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No fusible links at all. Just a wht/red and wht/blk wire on loops connected to + terminal. Will get a camera on it tomorrow and figure out how to upload.

Got BATT light on guessing due to over charge. One wire out of ALT going off to nowhere after plug. Bit of a birds nest but never had to mess with it. Got truck not running and replaced all mechanical parts that are replaceable in brakes engine and transmission. Not too worried about cosmetics but this electrical will be my next obstacle on this thing.

To my understanding one of the fusible links supplied power to most of my fuses so i was going to try to get that figured out.

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Get a free photo hosting account... other than Photobucket. There are lots like but not limited to... imgur or imageshack. Download your pictures there and store them. When you want to use one go there and copy the picture information bring here and paste into your post.


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Put a gauge on the fuse box The first 5 fuses on the left towards the driver's door should come on with the ignition key. 6 and 7 are also on in the accessory position. 8-13 are hot all the time and are on one of the missing links, leaving fuse 14&15 for headlights only and hot at all times and on the 3rd missing link..

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I have a D21 sitting in driveway. Completely untouched harness and emissions. Here are pics of the fusible links as they should be. The fist pic has the 4 wires that are directly on the terminal in the 720. Welp cant get the pics to work now. getting about 1/2 a volt with ignition on to fuses 8-11 Have aftermarket headlights and stock hi beams work. No tail lights or stop lamp. grounded temp wire doesnt make gauge jump. No fuel pump. BATT light on.

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You have a 720 which has it's own fusible links. (3 two Green and a Black)They are basically slow blowing fuses to protect the harness. I have no idea what rating the D21 uses but if higher than the 720 there's no protection. In an accident your harness might over heat and catch fire because the 'fuse' is too heavy.

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