Trans wiring damage

[321erace]

1997 Navistar 3800 DT466e with Allison 545 trans. So, I’ve been picking away at my bus to get it back on the road. Sat for several years on a farm. Ran when parked. I’ve got it starting and running now. Still repairing some brake lines so haven’t moved it under its own power yet. , I still need to figure out the trans wiring issues. Before I could get the bus towed off the farm, they fenced goats around it that chewed all the wires from the driver side harness to the starter and trans. I’ve spliced and repaired all of the starter wires, but still have three sensors/connectors on the trans that I don’t know how they’re wired to the harness. Speedo sensor seems to still be there and connected. Haven’t driven yet to confirm it’s working.On drivers side there’s a sensor right behind the shift linkage with two pink wires coming out. Goes to ? There’s 2 six inch pink wires coming out of it and then the rest was chewed off. Also have an electronic modulator on the driver side. Two inches left of 2 white wires from the connector to that, the rest is gone/eaten. Also have a sensor on the passenger side of the trans. That has about a foot of harness with two wires, 1 black and 1 white that comes over the top of the trans to the driver side and then was eaten. All I have out of the body harness are a few two or three wire connectors that are all unplugged. Not sure what they went to, if the were for all the extra safety lights, etc before bus was decommissioned and sold? Anyways. I’m at a loss as to what goes to where on the trans. Anyone have a similar bus that can take some pics or know where I can find a wiring diagram? Any help is much appreciated. Thanks

 

[s2mikon]

Picture 3724 is the neutral safety switch and the modulator, the large black thing. Picture 3726 is the reverse light switch. 3725 is a speed sensor. Speedometer maybe or road speed governor. Not sure. If you just need to move this and are in a hurry to keep the goats from eating any more just drive it out. It will run with out the modulator connected just don’t use it over half throttle. And I would take a few of their dead goats to the locker.

 

[BamaBus]

I don't see where your wiring for the trans starts, so I can't tell if what I took pictures of will help. My pictures are from a 98 (single box ecm) and my 97 (3-box ecm) is covered in mud. So I don't know if the leads to the trans are the same.
I have a bundle in a wiring loom that I failed to find where they start from. It has 4 sets of two wires leading to 4 areas of the trans.

Wires Leading to the safety switch



Wires leading to modulator


Speed sensor



Reverse light. Starts on drivers side end on opposite side

 

[321erace]

Thanks so much for these. There’s hope yet to figure this out. These pics are great. I will have to check under my bus as to what wires I have left and where they come from on the chassis. It looks like all of these wires on yours are coming out of the same smaller sheathed tubing, not the main harness, correct? Is that coming down from above the trans from the ecu box on the firewall?

 

[BamaBus]

Thanks so much for these. There’s hope yet to figure this out. These pics are great. I will have to check under my bus as to what wires I have left and where they come from on the chassis. It looks like all of these wires on yours are coming out of the same smaller sheathed tubing, not the main harness, correct? Is that coming down from above the trans from the ecu box on the firewall?

The wires branch off from the large mass of wires from the ecm, fire wall connection, etc. Then there is a small bundle that is above the starter leading to the rear. I counted 13(?) wires in the small bundle on a '99 but they could branch off again just out of sight.

Verified the same wire bundle on a '98 and a '97, which is in the same place regardless of the ecm type (3box vs single box).

The colors and wire numbers are not visible in my photos probably due to some paint in the area applied after a Weller trans install. However the wire color and numbers are visible under in loom. There are also two wires from the same general area in the frame that lead to the fuel tank.

FYI I have the exact same issue on an '02 with the 2000 trans. I always thought my dogs did the chewing, but last year I did allow my goats to free range!

 

[ewo1]

1997 Navistar 3800 DT466e with Allison 545 trans. So, I’ve been picking away at my bus to get it back on the road. Sat for several years on a farm. Ran when parked. I’ve got it starting and running now. Still repairing some brake lines so haven’t moved it under its own power yet. , I still need to figure out the trans wiring issues. Before I could get the bus towed off the farm, they fenced goats around it that chewed all the wires from the driver side harness to the starter and trans. I’ve spliced and repaired all of the starter wires, but still have three sensors/connectors on the trans that I don’t know how they’re wired to the harness. Speedo sensor seems to still be there and connected. Haven’t driven yet to confirm it’s working.On drivers side there’s a sensor right behind the shift linkage with two pink wires coming out. Goes to ? There’s 2 six inch pink wires coming out of it and then the rest was chewed off. Also have an electronic modulator on the driver side. Two inches left of 2 white wires from the connector to that, the rest is gone/eaten. Also have a sensor on the passenger side of the trans. That has about a foot of harness with two wires, 1 black and 1 white that comes over the top of the trans to the driver side and then was eaten. All I have out of the body harness are a few two or three wire connectors that are all unplugged. Not sure what they went to, if the were for all the extra safety lights, etc before bus was decommissioned and sold? Anyways. I’m at a loss as to what goes to where on the trans. Anyone have a similar bus that can take some pics or know where I can find a wiring diagram? Any help is much appreciated. Thanks

Hey, best thing you could do is call an International dealer parts dept. and ask them for a circuit diagram for the transmission wiring circuit.

 

[321erace]

I have gotten most of the wires figured out now from the pics and info you’ve supplied. Thanks so much Bamabus. The only things I’m not sure of are with the modulator connector. I assume polarity matters on the two wires going to this? Any way to tell or show me which way the three terminal connector (with only two wires l) attaches to the two terminal connector that plugs directly into the modulator? That plug at the modulator has two white wires coming out.
I have also found two more severed wires in a separate two wire pigtail that branches off the harness from the ecm to the trans. They don’t seem to go to the fuel tank because that is still connected to its own small pigtail. Any idea where these may have gone to? I can’t find any other unplugged connectors, sensors or wires that it could have been to. Contains two thinner (16-18gauge?) wires. 1 white and 1 orange or pink (very faded, hard to tell original color) it’s shown in the new pics

 

[BamaBus]

from the recycle bin


The connector to nowhere


I'll check another bus tomorrow and see if I can find a better color/number identification.

 

[321erace]

Maybe I had the same connector to nowhere? At this point connector has been eaten, so maybe just two wires to nowhere…

 

[cadillackid]

the modulator ahould be marked with a + and a - on it.. mine was..


I had a spare 2 pin connector in the harness that was for a transmission temperature gauge

 

[321erace]

Thanks for all the replies. I was thinking the extra wire pigtail may have been a temp sensor connector to the external filter/ cooler lines, but could not find anyplace it would have attached. Maybe was a feature for a different trans option? And I’ll look again at the modulator tomorrow and see if I can tell polarity from any markings.

 

[cadillackid]

I’ve seen the temp sensor in 2 places, one is a T fitting in the cooler OUT line on top of the transmission and the other is a pan mounted sensor.. the sensor then went to a dash gauge that fit into the gauge cluster .. the harness seems to be present on many of the chassis

 

[321erace]

Ok, so the modulator is marked for polarity, left side + right side - I suppose the only thing I’m left needing to know is which side of the three prong connector from the bus that is spliced to the two prong that plugs into the modulator is pos and neg. Only two terminals of the three are used on the three prong connector.

 

[BamaBus]

Ok, so the modulator is marked for polarity, left side + right side - I suppose the only thing I’m left needing to know is which side of the three prong connector from the bus that is spliced to the two prong that plugs into the modulator is pos and neg. Only two terminals of the three are used on the three prong connector.

The wire you are holding in the "c" position is the white/neg. You are holding the modulator side of the coupling.



Did the wires to the air dryer also get chewed?

 

[321erace]

Thanks Bamabus, that was what I needed to know. This bus is juice breaks only, don’t think there is an air dryer. I did find a few other victims of the goats though. Temp sensor had one wire still dangling that I repaired, but the temp gauge still isn’t working. Upon further inspection found two chewed more wire stubs in that area. I thought there was only one terminal to the sensor, since that’s all that’s in the three terminal connector, but I have to assume these other two wires went to it as well and the terminals got ripped right out. Anyways, I’ve got three pink wires from the harness that I assume all go to a new three terminal temp sensor connector. Found and ordered one that looks the same for a 97 Corvette LS1. I suppose my question is do you have the same temp sensor and can confirm three wires to it?

 

[nikitis]

My wife wants me to park my bus on our land.

I know there are field mice there. Is there any kind of protectant I can spray my underside of my bus with or engine with to push them away if stored there?

 

[BamaBus]

I suppose my question is do you have the same temp sensor and can confirm three wires to it?

Yes on the 97 it's 3 wires, same color and I couldn't find wire id. On the '99 it's 2 colors with id- 97CY4 goes to the 'B' position, 97BK goes to the 'C' position, 97DC5 goes to the 'A' position, as best I can tell.


Part Number 1678137C1 looks similar.

EDIT: It looks like your connector is still attached to the sensor.

 

[BamaBus]

If you can get into the harness for the trans wires, I found wire id on the '99 with the 545 trans.

97P goes to safety switch (rear)
97AU goes to safety switch (front)

71A(connects to white wire in connector) and 71 go to far side of trans.

92C and white wire(ID ?) goes to modulator. White wire eventually goes to ground on block.

47A and 47 (connects to two black wire in connector) goes to speed sensor top of trans.

 

[321erace]

Amazing. Thanks again! I will have to pull back the wire loom and see if there’s any ID markings on the wires out somehow figure which three wires go to which three terminals.

 

[321erace]

Also found this out of the driver side harness on out to the hood. Maybe the other end of this connector was chewed off? There’s a gray and white wire on the side that has the connector and then a chewed up gray and white wire where I assume the other end of the two terminal connector was?