Wiring harness early model/late model

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jahrafa
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Wiring harness early model/late model

Post by jahrafa »

Hello,

I purchased an NOS wire harness with Douglas connectors and I am trying to install it in my project. I bought it thinking that there was no difference between early and late models other than the connectors themselves. I believe my vehicle is the late model B1 because the person I bought it from said it was a '58 but I am unable to see the date on the data plate. The previous owner had so many layers of paint in the plates of different colors that I am trying to figure out how to remove it without damaging them.

Anyway I was looking at a wiring chart on a previous old post in the forum and I found that some of the wire numbers on the harness I purchase are not the same as described in the old post chart. It seems like they are for the same things but different number. I noticed that there are circuit breakers behind the instrument panel and are for Douglas connectors.

My question is: is the main difference between the late and early harness the connectors being Douglas or Packard? or are the wires also directed to different things? or are they use for the same things but different numbers of some wires?

I am trying not to loose the money I paid :(

Thank you in advance,

Rafael
jahrafa
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1952 M38, 1952 M37
RCrombie
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Re: Wiring harness early model/late model

Post by RCrombie »

One of the main differences is the addition of turn signals on the later trucks. Otherwise they are pretty similar.
Can you look at the part number of your NOS harness and see if it is in fact for an M42 or something? They had some extra equipment.
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Argie1978
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Re: Wiring harness early model/late model

Post by Argie1978 »

jahrafa wrote: Sun Nov 20, 2022 9:47 ambut I am unable to see the date on the data plate
Haven't you checked the serial on the frame and the corresponding date range in the manufacturing dates page?
As said, harnesses are almost identical apart from the turning lights. You'd need to distinguish between the terminals for the surgical lamp and the dome aim for the ambulance.
Sebastian
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vargaspj
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Re: Wiring harness early model/late model

Post by vargaspj »

Rafael, what is your truck's serial number that's stamped on the front frame rail (should be eight digits; for example 80011151)?
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