M1026 Wires 458A, B, C & D

[kfrosty]

I'm having issue with the temp gauge on one of my -9-2320-280-34 I see 458A in several places.

One place it states connect these to the fan clutch temperature switch in the water crossover. (Edited this as I thought that was the to the actual water temperature gauge.

Yet, in section 3-25 it states connect 458As to 458C & 458D. Engine is a 6.5. In my other vehicles I don't see a 458C & D.

My quandary is trying to figure out what exactly connects to my water temperature sensor and go from there.

I've tried a different water temp sensor, haven't switched out the gauge or figured out how to check for current at the gauge just yet.

 

[kfrosty]

Actually wire 33B is the wire that goes to the Temperature sending unit. The temperature sending unit for the temp gauge is on the left head under the alternator. Diagram is in TM 9-2320-280-34 section 3-4

I still don't know what to do with 458C & D. I have a wire 568 Think it's 568B, if anybody has any ideas, it would be appreciated. I'm going to keep searching.

 

[Retiredwarhorses]

Actually wire 33B is the wire that goes to the Temperature sending unit. The temperature sending unit for the temp gauge is on the left head under the alternator. Diagram is in TM 9-2320-280-34 section 3-4

I still don't know what to do with 458C & D. I have a wire 568 Think it's 568B, if anybody has any ideas, it would be appreciated. I'm going to keep searching.

458 has 2 leads that come out of the thermostatic fan switch on the left of the water crossover....those connect to 458A and 458B, makes no diff which side you plug into on 458.
458B also goes to the TDM in the harness...so when the temp hits 215ish it closes or open to provide or deny 24v to the TDM...can't remember whcih right now. I think it's alway go 24v, then opens and Denys voltage. The same is if you unplug the TDM from the Cadillac valve.

 

[Retiredwarhorses]

A high restistance short will cause the temp gauge to fail or be flakey. I had one where the wire from the block sending unit was bad...just run a wire direct from it.
33A is from eng temp switch
58E is ground
27G is power to gauge.

those gauges are junk...had lots flake temp Gauges.

there is a procedure in the book for TS the gauges...

 

[kfrosty]

458 has 2 leads that come out of the thermostatic fan switch on the left of the water crossover....those connect to 458A and 458B, makes no diff which side you plug into on 458.
458B also goes to the TDM in the harness...so when the temp hits 215ish it closes or open to provide or deny 24v to the TDM...can't remember whcih right now. I think it's alway go 24v, then opens and Denys voltage. The same is if you unplug the TDM from the Cadillac valve.

I figured that out but there was a section in the TM that stated 458A & B to 458 C & D. But in other areas it states hook the fan temp switch to 458A & B.

But now I have 458C & D which I'm trying to figure out where they go.

 

[kfrosty]

A high restistance short will cause the temp gauge to fail or be flakey. I had one where the wire from the block sending unit was bad...just run a wire direct from it.
33A is from eng temp switch
58E is ground
27G is power to gauge.

those gauges are junk...had lots flake temp Gauges.

there is a procedure in the book for TS the gauges...

From the TM.
Disconnect harness lead 33B ( from engine temperaturesending unit (7).
Left head at front.

I found 33B wasn't even hooked up to the sending unit, hooked it up and the gauge started working.

 

[kfrosty]

Also, the best I can tell, 458C & D come the transfer case for a indicator light which I don't have and haven't seen one in a Hmmwv as of yet. So I guess I'll just cap them.

 

[Retiredwarhorses]

Also, the best I can tell, 458C & D come the transfer case for a indicator light which I don't have and haven't seen one in a Hmmwv as of yet. So I guess I'll just cap them.

those are the power supply leads to the 242 tcase lock lamp...if you don't have the Tcase, you don't need to connect them. just do as I previously stated on 458. If you want..
remove that tcase harness and I will buy it...it runs from the engine area to the Ste/ice connector area and then to the tcase where there will be 2 leads.

 

[Retiredwarhorses]

Let me add...I have seen the harnesses installed with 242's and they never drill the lock lamp hole and installed the lamp....must mot have had a big enough drill bit...you sure you don't have a 242?

 

[kfrosty]

Let me add...I have seen the harnesses installed with 242's and they never drill the lock lamp hole and installed the lamp....must mot have had a big enough drill bit...you sure you don't have a 242?

I do have a 242. I think all 4 of mine have 242's, just haven't seen this wiring harness and none of the 4 have a transfer indicator light in the dash to my knowledge.

So the question is finding a light, plugging the wires, taking it off etc.

 

[Magnanimous]

I figured that out but there was a section in the TM that stated 458A & B to 458 C & D. But in other areas it states hook the fan temp switch to 458A & B.

But now I have 458C & D which I'm trying to figure out where they go.

Did you ever figure out what to do with it

 

[pig9r]

Sorry for raising a dead post but i am hoping some one can provide an answer for the next guy to search this.

I am finishing up a 4l80e swap on a truck that had a 6.5 and 242 paired to a 3l80. The 242 transfer case wiring harness was there along with having the T/C Lock light mounted but the connectors on the transfer case harness at the motor end were plugged into each other near the coolant crossover. I believe they are labeled 458 c and d. I have searched TMs and all over the inter webs and came up empty handed. Must be top secret stuff. Any help would be appreciated. Thanks!

 

[Action]

Sorry for raising a dead post but i am hoping some one can provide an answer for the next guy to search this.

I am finishing up a 4l80e swap on a truck that had a 6.5 and 242 paired to a 3l80. The 242 transfer case wiring harness was there along with having the T/C Lock light mounted but the connectors on the transfer case harness at the motor end were plugged into each other near the coolant crossover. I believe they are labeled 458 c and d. I have searched TMs and all over the inter webs and came up empty handed. Must be top secret stuff. Any help would be appreciated. Thanks!

You can just open a pdf TM and click the magnifying glass. Enter "458c" and hit the ENTER key on the keyboard.
TM 9-2320-280-20-2 shows 458B and 458C going to the fan temperature switch. The 2 wires from the transfer case light switch are 511A and 511B.
TM 9-2320-387-24-2 shows 458A and 458B at water temperature sending unit. The picture shows 458C and 458D connected to 2 of 458A near the alternator.
What is the transfer case wiring harness?

 

[pig9r]

You can just open a pdf TM and click the magnifying glass. Enter "458c" and hit the ENTER key on the keyboard.
TM 9-2320-280-20-2 shows 458B and 458C going to the fan temperature switch. The 2 wires from the transfer case light switch are 511A and 511B.
TM 9-2320-387-24-2 shows 458A and 458B at water temperature sending unit. The picture shows 458C and 458D connected to 2 of 458A near the alternator.
What is the transfer case wiring harness?

Thanks for the info. I searched the same way and just got this graphic referring to 12, 13 and 31:



The transfer case wiring harness is part number 12342789.

Wire Harness For HMMWV Transfercase, 12342789

Wire harness for HMMWV transfercase. For use with transfercase 5937387 which was used on M1097A1, M1097, M998A1 and all other A1 variants. P/N 12342789. NSN 6150013625229. 0.5 lb

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