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| | | | Joined: Nov 2009 Posts: 110 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2009 Posts: 110 | The ignition switch in my 51 1/2 ton is not labeled and I can't tell which wire is supposed to go where. Can anyone post a picture of the back of their switch or a way to identified which prong on the switch is to be use for what? Mine is the original switch and it has three prongs on the back.
I tried testing it with power going to the off position prong and connected a light bulb to the second prong (which lit up when I turn the key to the first position, but the same didn't work when I turn the key to third position...is my switch working right.
Because of the way I tested it (which might have been wrong) How is the heater switch supposed to be wired to that prong if it always stays "off"? I was under the impresion that that prong fed power to the heater switch and then from the heater switch a wire ran up to the heater motor????
Please help me....I am so confused now!!! | | | | | Joined: May 2001 Posts: 7,438 Extreme Gabster | | Extreme Gabster Joined: May 2001 Posts: 7,438 | If your switch is stock the 3 positions are 'lock', 'off' and 'ignition'. In 'off' you can remove the key and still move the switch to 'ign'. I don't know what years those were used but , to ID one, it has a little tab on the face of the switch. By '53, this tab was gone and the switch just had 'locked off' and 'ign'.
Without looking at the manual I would suspect that one terminal is voltage from the battery and the other two are hot when the switch is on. One of these would go to the amp gauge and one to the coil. I'd hook the heater switch to the one going to the ammeter.
I highly doubt if the heater is in the wiring diagram in the manual. | | | | | Joined: Jul 2001 Posts: 3,887 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Jul 2001 Posts: 3,887 | 51 truck wiring diagram here - should be one in your shop manual Bill | | | | | Joined: Nov 2009 Posts: 110 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2009 Posts: 110 | Cletis, that "lock, "off" "ignition" info was good that help me some.
| | | | | Joined: Nov 2009 Posts: 110 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2009 Posts: 110 | The diagram is great, I have a super sized version of it and color coded on the wall. My problem is actually identifying the right prongs in the back of the ignition switch to connect them. | | | | | Joined: Jul 2001 Posts: 3,887 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Jul 2001 Posts: 3,887 | well there's only 2 terminals shown as used on the diagram and it sounds like you found the 2 that make for of/on, your problem is thinking the heater is supposed to hook on the third .... just ignore that 3rd terminal and take the heater power from the one that's hot when the key is on .... and use an inline fuse
Bill | | | | | Joined: Nov 2009 Posts: 110 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2009 Posts: 110 | Bill, I am very greatful. You put it on simple terms for me. This whole electrical thing is new to me and I am trying to get it a fast as possible...Thank you again well there's only 2 terminals shown as used on the diagram and it sounds like you found the 2 that make for of/on, your problem is thinking the heater is supposed to hook on the third .... just ignore that 3rd terminal and take the heater power from the one that's hot when the key is on .... and use an inline fuse
Bill | | |
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