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1985 D-350 Crew Cab w/ 89 12V 4x4 swap, 315hp marine ppump, 370 injectors, BW k27, G360
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Discussion Starter · #1 ·
To start I have searched to forums and tested a few things.
Right now everything in the truck functions except starting with the key. The wiring is all from the 1985 D350 with a transplanted 89 Cummins. Ran awesome until I went to leave a car show turn the key everything turned on, turned to start and nothing. So quick trouble shooting at the show and I just jumped the wire at the starting relay (so I didn't have to crawl under the truck with a screwdriver). The starting relay ground pin is hardwired to ground thus removing the neutral safety switch. If it matter this truck is a manual swap as well.

I tested the relay at home by jumping 12v straight to the ignition wire on the relay = truck fired right up.
I tested the plug under the dash by jumping the 12v to the ignition switch to the signal wire that leads to the relay = truck fired up again
Replaces the ignition switch and have the same problem, turn the key to start and nothing. So I jumped the connections at the back of the switch directly and the truck fired to life.

Anyone have an idea why two ignition switches would not send the ignition signal to the starter relay? Does the ignition switch somehow act like a relay/solenoid?
 

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Is the starter relay grounded good, the older style on the 85's had to be.
 
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Not a Dodge man but do these have a steering lock attached to the switch?
Have you tried the switch on the wiring without installing in position.
 

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1985 D-350 Crew Cab w/ 89 12V 4x4 swap, 315hp marine ppump, 370 injectors, BW k27, G360
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27 Posts
Discussion Starter · #4 ·
Is the starter relay grounded good, the older style on the 85's had to be.
I have to believe so because if I jump the pins on the switch. Power into switch jumped to start signal out to the relay the truck starts. Doing this sends the signal through the firewall to the relay then the starter.
 

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1985 D-350 Crew Cab w/ 89 12V 4x4 swap, 315hp marine ppump, 370 injectors, BW k27, G360
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27 Posts
Discussion Starter · #5 ·
Not a Dodge man but do these have a steering lock attached to the switch?
Have you tried the switch on the wiring without installing in position.
These do have a steering lock. I tested the switch while the column was all taken apart, so the lock was removed. Then I put it almost all back together, lock in place and no change.
 

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1985 D-350 Crew Cab w/ 89 12V 4x4 swap, 315hp marine ppump, 370 injectors, BW k27, G360
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Discussion Starter · #6 ·
Here is a visual for how I jumped the switch. I did this while the switch was out and I could jump the pins on the back of the switch itself. This made the truck start
Schematic Font Line Parallel Technical drawing
 

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My boss has a 79 d150 at my job that wouldn't start with the key and it had a connector that looked like the one in your diagram.

The problem turned out to be a bad fuse link, because there are actually two power wires feeding into the ignition switch. One provides power for the accessory and run contacts but the other exclusively provides power for the crank(start) contacts.

It fooled us for well over an hour, because we were convinced we had power getting to the ignition switch, but we only had one power and it requires two.

Perhaps that is the case on yours also.
Good luck.
 
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1985 D-350 Crew Cab w/ 89 12V 4x4 swap, 315hp marine ppump, 370 injectors, BW k27, G360
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27 Posts
Discussion Starter · #8 ·
My boss has a 79 d150 at my job that wouldn't start with the key and it had a connector that looked like the one in your diagram.

The problem turned out to be a bad fuse link, because there are actually two power wires feeding into the ignition switch. One provides power for the accessory and run contacts but the other exclusively provides power for the crank(start) contacts.

It fooled us for well over an hour, because we were convinced we had power getting to the ignition switch, but we only had one power and it requires two.

Perhaps that is the case on yours also.
Good luck.
I will looking to this in the wiring diagram to see if there is another power line while off. I know one line comes from the charging system, not sure if that one is powered while not running though.

There are a lot of wiring issues in this truck. Since this went from gas to diesel, auto to manual but all the original wiring is still in the truck. Its slow picking to find what to trim and what not to trim.
 

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Font Line Handwriting Parallel Pattern


Here's the diagram from the 79 and 80 models. As you can see on that banana shaped connector the very first pin is battery voltage it's a 12 gauge red wire.

Also the third pin is battery voltage feeding the switch it's a 12 gauge pink and black wire.

On the 79 models they are fed independently through fusible links, the one that popped on my boss's truck was the one that exclusively feeds the contact for cranking the starter.
 
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Discussion Starter · #10 ·
View attachment 955339

Here's the diagram from the 79 and 80 models. As you can see on that banana shaped connector the very first pin is battery voltage it's a 12 gauge red wire.

Also the third pin is battery voltage feeding the switch it's a 12 gauge pink and black wire.

On the 79 models they are fed independently through fusible links, the one that popped on my boss's truck was the one that exclusively feeds the contact for cranking the starter.
If I'm reading this correctly, one power feed is to the starter (red) when the key is turned to "start" and the other (pink/black) powers everything else on the ignition when in "acc" or "run".

So when I get a chance I'll check to see if I have battery voltage at both pins in the connector.
 

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Hello,

We see that you have received some great advice from your fellow forum members! However, if these suggestions do not address your concern and you decide to visit your dealer, our team would be happy to offer additional assistance throughout that process! We're available via private message

Callie
Ram Cares
 
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