m38 early style switch

circleburner12 · Post by **circleburner12** » Thu Mar 20, 2014 4:57 pm

well karma came back to bite me today, to punish my son for not doing his homework because of the video games. I made him help me on the jeep, told him to use his hands to take the headlight switch out of the dash instead of a joy stick. well he did! he took the front of the switch off, when he did parts came off and out of place.

so is there anyone willing to put this switch back together and make sure it works. will pay for shipping both ways and for the trouble. or would it be best to find a single connector switch?

thxs

Post by **wesk** » Thu Mar 20, 2014 7:34 pm

All the directions are right here in the downloads section: http://www.willysmjeeps.com/v2/modules. ... it&lid=139

Kendall · Post by **Kendall** » Fri Mar 21, 2014 7:17 am

I took one apart and put it back together. It is a little aggravating but it can be done. I used a spot of super glue on those little springs where the contacts fit into them. Then it is like installing them as one unit instead of two.
Kendall

skyjeep50 · Post by **skyjeep50** » Fri Mar 21, 2014 7:38 am

If your jeep is wired to use the early style light switch with the double plugs you will have to stick with the early style switch or modify your existing wiring harness to adapt to the single plug type. The second plug is for the trailer light harness. See: http://www.willysmjeeps.com/v2/modules. ... ght+switch

circleburner12 · Post by **circleburner12** » Fri Mar 21, 2014 4:28 pm

kendall I would prob screw it up worst then it is already.

skyjeep, someone before me chop and made a mess out of the harness and most is gone. I do however have a brand new wiring harness dated 1953 and was hoping to use it. but some say it will work with a single plug switch and others say I will have to modify it to work. I really don't have a problem going to a single switch if this harness would work without cutting and adding longer wire. thxs

Post by **wesk** » Fri Mar 21, 2014 7:34 pm

What is the part number of your new harness?

The early Bendix-Scintilla switches were of much better quality than the later single plug switches. Plus parts can be found for the early switches and they were built to be maintainable. The TM 9-1825E I linked has all the details for rebuilding the switch and testing it.

circleburner12 · Post by **circleburner12** » Sat Mar 22, 2014 7:00 am

heres the box tag info.

osn g758-83-29662

wo-806410

da-33-019-ord-1268

burton packaging company

date-11-53

Post by **wesk** » Sat Mar 22, 2014 7:43 am

That is a light switch harness for the M38A1. The light switch to the front and rear lights. It is meant for use with a single plug late light switch.

skyjeep50 · Post by **skyjeep50** » Sat Mar 22, 2014 8:05 am

Here's the 5 second confirmation test. Look at your new (old) harness and see if it has two canon plugs where it connects to the light switch - if it does, it will work with the old style light switch. If it has only one, it was designed to work with the new style switch. Canon plugs are the screw on multi-pin connectors that hold the wiring bundle to the back of the light switch. The light switch plugs are distinctive and are found at only one location in the bundle.

Post by **wesk** » Sat Mar 22, 2014 8:28 am

Not the best way to ID a harness. The firewall harness also has a multi-pin plug that goes on the regulator.

All M38A1/M170 light switch harnesses have a single 12 pin plug at the switch.

Original M38's light switches to MC35387 (Sep 51) have two plugs. One 12 pin plug for front lighting harness and one smaller 6 pin plug for rear lighting harness (these two harnesses have seperate part numbers and pass through two seperate holes in the firewall. M38's from SN MC35387 through MC65927 use a different single 12-pin plug light harness and MC65928 & on use another single 12-pin plug light harness.

The point here is if you are holding a NOS M38 single plug light switch harness in your hand it may any of the three single plug switch harnesses or it may be the first M38 front light harness, all of which have a single 12 pin plug.

Also the Metal wire number tags will all be for lighting system components except one #15 for + 24V.

circleburner12 · Post by **circleburner12** » Sat Mar 22, 2014 10:55 am

yes it has one plug, and is for a m38a1. like I said earlier it would not bother me to go to a later style switch if for sure I knew the a1 harness would work on the m38 if I go to a single light switch. thxs guys

Post by **wesk** » Sat Mar 22, 2014 11:17 am

I see no reason the M38A1 harness would not work with the M38 with any of the three light switches with the only exception being length of some wires which is an easy adaptation to make.

That large 12 pin connector does the same job on all three switches. On the first series M38 with the two plug switch the pin functions on the small 6 pin plug are duplicated on the large 12 pin plug. They were just not used on the large plug on the harness side.

Here are the pinouts for the early switches and the corresponding harnes part numbers:

circleburner12 · Post by **circleburner12** » Sat Mar 22, 2014 5:12 pm

ok thxs guys, now I need to decide which switch to go with. if I do buy a new harness I think I will go ahead and get the turn signal option. wish I would have on the a1. thxs again

Post by **Ryan_Miller** » Sun Mar 23, 2014 2:07 pm

You can do it. I took one apart once and cleaned the contacts. It takes an extra hand to keep the contacts on their springs while putting the cover back on.

skyjeep50 · Post by **skyjeep50** » Mon Mar 24, 2014 9:50 am

If you can get the original switch back together and it works ok it will probably serve your jeep for decades more. You can order a new harness with the turn signal harness and one which will accomdate your old light switch. When I replaced the harness on my M38 I went to the single plug light switch (with provisions for the electronic turn signals) mainly for redundancy between my '53 M38A1 and '51 M38. I had participated in a summer educational day at an area school a few years back - also on the program was a bob-tailed '72 M35 and a Hummer. The M35 and my jeep had the same light switch, the Hummer had the push button style but I bet I we could have exchanged light switches between all three vehicles and they would have worked just fine. Standardization certainly has its place.