YOREL

I have my dash apart to replace the odometer gears and am also going to do the "Jim Lane Blower Motor Relay Mod" while I am in to it too. Is there also a write up on putting a relay setup in to take the load off of the ignition switch? I searched the stickys and the forum but didn't find any thing. Maybe I missed it. If there is a write up could it be put in the stickys for future reference? Thanks in advance!

ppiggppenn

Good plan, ... I added the fuel solenoid to the relay running my marker lights, but you could grab the wire for your fuel sol and use it as the trigger wire on a relay running the fuel sol. This can be done just under the hood with no dashboard dismantle.

BearKiller

At the column, find the "cold" side of the KEY-ON=HOT and treat it in the same manner that you did the head-light relays.

There is some considerable amperage going through that circuit, as in the wiper-motor and blower-motor, so a constant-duty solenoid is a better choice than a relay; it does the same job, just much more heavy-duty.

YOREL

Good idea on the CD solenoid. I have extra grid heater solenoids that I just might use for this project. I have been studying the wiring diagrams and it appears that there are actually 3 separate power feed circuits that are routed from the ignition switch. Two are 14 gauge wiring and one is 12 gauge wiring that feeds just the power windows and blower motor. I think I am going to just relay the 12 gauge circuit for now using a grid heater solenoid and then possibly take on the other two 14 gauge circuits later. I might be able to use a large Bosch relay for these two circuits. Thanks again!

BearKiller

Split the power-window circuit away from the KEY=ON=HOT wire at the fuse-block and replace the window feed with a separate 10-AWG ALWAYS-HOT wire.

Hence, you can operate the windows regardless of key position.

chaikwa

That's what I've done on every truck I've owned, mainly because I ran a lot of emergency lights as a firefighter. When I got to the station or the scene and wanted to shut the truck off, I didn't want to be bothered shutting off 4 or 5 switches. So Everything that didn't come stock with the truck got wired to a constant duty solenoid activated by the fuel wire. When I shut the key off, it shut everything else off too.

A side benefit to the CD solenoid is that if you ever DO have a wiring problem, once you shut the key off the electrical problem goes away, (as long as it's a problem associated with an accessory). This just might save a truck from a fire.

roysleight

Be careful with putting the power window circuit on always hot fuse. There are switch lamps on each door that will cause a constant draw on the batteries. Could be a problem if the truck is parked for extended periods or in cold climate.

BearKiller

Please explain further about these "switch lamps" ??

I am unaware of the existence of such.

Although my preference is manual windows, there have been a few power-window trucks that have made it into our fleet.

Every single one of these has had the power-windows re-wired to always HOT and in many years I have thus far never had any negative issues.

ofcmarc

On a newer Generation truck, There are little LEDs or some such that illuminate the window switches from behind/inside. No such monster on a 1st gen.

YOREL

Some very good suggestions! I was planning to install a 2nd Gen power distribution center I pulled at the scrap yard and using it to replace the wire type fusible links and also use the considerable number of relays for headlights and such. But now after thinking some more, since almost all of the truck wiring is ran through a fusible link anyway (except for starter feed), if the power to the distribution center was first ran through a large amp continuous duty solenoid (heater grid relay) which was activated by a discreetly placed switch in the cab, I would have a "poor man's security system" since even with a key, without tripping the switch for the solenoid first the truck would still be dead. The only circuit that would need power 24/7 would be for the radio station memory. Also, I don't believe the ECM in my 92 is of the type the has to relearn after power interruption. Also, this way the truck would be guarded against any battery drain or middle of the night wire fires! Even the alternator output could be placed on the cold side of the CD solenoid to protect against possible blown diodes. What do you think?