Fuse block. Ignition and keyed power. Help me please

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Timmy adkins

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I am so confused. I have my battery wire running to the battery from the fuse block. I have my pink wire running to my underwood fuse block for my ls swap.

Here’s where it gets weird. There is a little range wire under the dash the lugs into one of the battery slots on the fuse block. It powers the door buzzers and map light. When I have the plugged in, my test light reads hot to the body of the truck. Is this normal? Light goes off when the buzzers are pushed in.

Secondly, and most confusing. When I unplug that orange wire, I have zero power on the keyed power wire and purple ignition wire no matter what position the key is in. Now when I plug it in, it seems like the pink wire has constant power running to it. The test light is very dim. I’ll attach a picture. Then when I put the test light on the ignition wire it burns dim when the key is in the start position. I made sure it was in park. I don’t have the starter hooked up or anything like that. I’m just trying to get my wiring right.

I suspect a bad ignition switch based on the fact that it is even allowing power in the slightest way to the pink wire with the key off. And when that orange wire is unhooked it’s doing nothing.

Has anyone dealt with this?


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chengny

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I have my battery wire running to the battery from the fuse block.


As wired stock, there are two battery feeds to the bulkhead connector (and then into the cab). Both are connected to the battery positive cable at the "B" terminal on the starter solenoid. The connector of each lead (solenoid end) includes a fusible link to protect the circuit (s) that it supplies.

One runs straight from the solenoid to the bulkhead connector (circuit RED 2J). In the cab it splits into two branches. One branch goes to the fuse block and feeds the T/L CTSY & HORN DM fuses. The other leg goes to the headlight switch and supplies the main beams.

The other power supply from the solenoid connection (RED 2B) is connected to the line (inlet?) side of the junction block - which is located on the firewall. On the load side of the JB, the circuit that goes to the bulkhead connector is then called RED 2E. This circuit is protected by an additional fusible link that is located near the JB end of the lead. After transiting the firewall - at the bulkhead connector - the RED 2E lead is branched off into 3 legs. Two of those legs (2E & 2C) feed the ignition switch on terminals BAT 2 & 3. The third branch leg goes to the fuse block and supplies the line sides of the STOP HAZ fuse and the PWR ACCY circuit breaker.

I have my pink wire running to my underwood fuse block for my ls swap.

I can't help you on this part because I have no idea what an "underwood fuse block" is - or what it does. If you're working with an aftermarket wiring kit maybe consult the vendor. Also, not sure of which "pink wire" you are concerned about? That isn't made clear. If I had to guess, I'd say you're talking about the power supply from the ignition switch to the ignition coil primary - at the B+ terminal?


Here’s where it gets weird. There is a little range wire under the dash the lugs into one of the battery slots on the fuse block. It powers the door buzzers and map light.


Wired as factory, the orange (range?) wire - the one plugged into the upper of the two BAT sockets - would go to the hot side of the dome light(s). And AFAIK there was never any such thing as door buzzers on these trucks. And by "map light", do you mean dome light?

Light goes off when the buzzers are pushed in.

IDK what light and buzzers you're referring to.

When I have the plugged in, my test light reads hot to the body of the truck. Is this normal?

With either door open, yes that would make sense. The dome lights always have power full battery voltage supplied on one side (via the ORN wire discussed above). When a door is opened the contacts in the door jamb switch close, which connects the other side of the lamp to ground. And in this case ground is through the the cab body - and then back to the battery negative.

When I unplug that orange wire, I have zero power on the keyed power wire and purple ignition wire no matter what position the key is in.


As mentioned above, the ORN wire that is plugged in to the BAT socket is power out of the fuse block and to the dome light. Unplugging it should have no effect other than disabling the dome light.

IDK what you mean by the "keyed power wire".

I guess when you say the the "PPL ignition wire" you mean the lead that comes from the NSS switch at the base of the steering column? On your model year, that circuit starts off as YEL 5 at the SOL terminal on the ignition switch. Only after passing through the contacts of the NSS does it become the lead PPL 6 - and then straight to the "S" terminal on the solenoid. The contacts close when the gear shift lever is in either P or N.


Now when I plug it in, it seems like the pink wire has constant power running to it. The test light is very dim. I’ll attach a picture. Then when I put the test light on the ignition wire it burns dim when the key is in the start position. I made sure it was in park. I don’t have the starter hooked up or anything like that. I’m just trying to get my wiring right.

I suspect a bad ignition switch based on the fact that it is even allowing power in the slightest way to the pink wire with the key off. And when that orange wire is unhooked it’s doing nothing.


There are just too many variables here for an "internet diagnosis". But I first would certainly check the ignition switch and also the dome light wiring for grounds.

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Timmy adkins

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I have figured out the ignition wires before your response. However, thank you for your response.

What I meant by “buzzers” are the door jam switches that sense when the doors are open and closed. These activate the dome light when the door is open.

I guess the thing that concerns me is why the test light aluminates when touched to the body of the truck


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AuroraGirl

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I've used a test light to test for grounds, you go from a positive source to metal. If you don't get light it means the material isn't conductive of too corroded. I believe. Unless I'm mistaking just completing a circuit now that I think of it so is the other way, I guess
 

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