Relay activated from controller by negative 10v(weak)

Tonyr1084

Joined Sep 24, 2015
9,744
Thanks for the clarity on what we're dealing with. Perhaps a full set of wiring diagrams would help.

As for selling something that is faulty - someone is going to have to bite the bullet on that one. Looking for a workaround isn't going to be quite so easy. The only thing I can think of is to put a second switch on the dash board. Use that to ground KR2. The only down side is that the operator will have to remember to switch it off when done.

I would have first suspected the turn signal (TS) lever. (also called a multi-function switch) They go bad too. But you said this is a common problem. If it's a common problem then the solution should be well known. Is your boss asking you to do something shady?

I'd like to know exactly what wire 032 provides. Looks like if you pull the lever back it flashes the high beams. But if you push it forward it's supposed to stay on high beams. Do the high beams come on when you pull back on the TS Lever? Another wire whose purpose is needed to be known is wire 158. Just guessing but that also should be power. But it looks like it's switched power from the headlights control switch. When in positions SW1, SW2 and SW3 power is available for the high beams. Power comes from wire 062, through the multi-function headlight switch (probably located on the TS lever). When the lights are on wire 158 has power. It goes to the TS at pin 56, through the switch and on to KR2.
 

Tonyr1084

Joined Sep 24, 2015
9,744
I think this Module will work with that controller to activate KR1
I think you meant to say KR2.
And we still don't know what kind of power is available on a wire that appears from the later drawings to provide power. If it's not providing power (not to be confused with voltage) then an additional relay might not work. And by "Power" I mean sufficient current to drive the module. It already is not providing enough power to trigger the relay (KR2). There may be voltage, but possibly not sufficient current.
 

Tonyr1084

Joined Sep 24, 2015
9,744
Instead of using a volt meter try using an automotive lightbulb. If the source can light a lightbulb then it should trigger the relay.
 

sghioto

Joined Dec 31, 2017
8,634
Module
Here's the wiring hookup using that relay module.
Hopefully this will work as the signal input requires only a few milliamps.
1736543032114.png
 
Last edited:

MisterBill2

Joined Jan 23, 2018
27,639
I have a radical suggestion which iis this: Forget the frame "ground" connection and run an actual ground wire. Then there will be no more "weak grounds" problems.
 

Tonyr1084

Joined Sep 24, 2015
9,744
I have a radical suggestion which iis this: Forget the frame "ground" connection and run an actual ground wire. Then there will be no more "weak grounds" problems.
It's a controlled ground. It's only there when lights are supposed to be on. Power comes in on KR1, pin 86. Pin 86 is always hot. If the TS grounds pin 85 the lights come on. but they stay on. When the system is shut down KR2 drops out and provides power to the high beams. That's the complaint.

And yes, @sghioto you're right. I had it mixed around. The second drawing didn't help either. It focused on wire 113, not 183.

Problem: KR1 is not activating when it should.
Cause: Unknown as of yet.
Solution: Resolve the commanded grounding issue on wire 183 or bypass it via some other means.

The TS has said:
Follow the 113 wire its taking ground from the switch.
Hence, my chasing the wrong rabbit. 113 provides power to KR2, not ground to KR1
 

Tonyr1084

Joined Sep 24, 2015
9,744
This is how I seem to be reading the problem. Note that wire 183's connections have not been established.
Screenshot 2025-01-10 at 2.54.44 PM.png
If KR1 pin 85 remains grounded the lights will be on until the battery is dead. IF we are to use line 183 we need to know where it goes and is connected to what. Can the TS show us where that wire goes? BCM? ECU? 's gotta go somewhere.
 

Thread Starter

Toolmakerr

Joined Jan 10, 2025
13
Several times the TS has made comments about problems with grounds. So the problem might actually be an open ground connection that is not recognized.
Evrythink else its working on the machine every other lights are working no DTC usualy if there is controller ground or power problem immediately gives a DTC.
This is how I seem to be reading the problem. Note that wire 183's connections have not been established.
If KR1 pin 85 remains grounded the lights will be on until the battery is dead. IF we are to use line 183 we need to know where it goes and is connected to what. Can the TS show us where that wire goes? BCM? ECU? 's gotta go somewhere.
Wire 183 is from the controller only thats why i didn't give a drawing on it but here it is anyway.A110x1 it is the CAB controller connector.The switches are fine cuz as i mention there is two types of Hi beam and low beams on the machine and on the hood once are working and i got a blue LED lighting up when i use the switch that indicates of lever is pressed yea they ussualy go bad here aswell but not in this case.In the lever drawing im not sure if power goes to KR2 with wire 113 cuz they are only triggerd by a ground even the "switch dots" are higher drawn.
Im sorry if i dont respond quicker but i have to make this pictures and follow up what i did yestarday so i can explain exactly what is going on.Thanks
viber_image_2025-01-11_11-46-23-726.png viber_image_2025-01-10_21-54-54-43434434333333653.PNG
 

Tonyr1084

Joined Sep 24, 2015
9,744
Thank you for the wiring diagram (the big picture). Unfortunately it doesn't tell us much. Here's what I've gleaned from the big picture:
The routing of wire #113 is as follows:
Starting at connector S927 (pin 56A) it goes to connector X101 (pin T) to X121 (A6) to X115 (D1) to X170 (B) to KR2 (86)
The routing of wire #183 is as follows:
Starting at A110X1 (F3) to X15 (D2) to X170 (E) to KR1 (85)
That's ALL the big picture gives us. No switching details or anything else.

In post #33 we are reminded that when you ground pin 85 of KR1 the lights are always on. See the quote below.
This is how I seem to be reading the problem. Note that wire 183's connections have not been established.
View attachment 340085
If KR1 pin 85 remains grounded the lights will be on until the battery is dead. IF we are to use line 183 we need to know where it goes and is connected to what. Can the TS show us where that wire goes? BCM? ECU? 's gotta go somewhere.
The other drawing you posted in post 36 again is showing us wire 113. We still don't know where 183 is going (aside from the routing of the big picture. Connector and pin to connector and pin. And that's a lot of connections. Any one of them could be loose and making poor contact.

So I'll ask again: Where does wire #183 go? We know when you hard ground it the relay works. But when you try to use it through the tractor wiring it doesn't. THAT is where we need to focus our attention.

Again, we appreciate your efforts in satisfying our requests. Please try to give us something like the smaller picture that shows wires #113 and #183 but complete wiring to the Multi-Function Switch (MFS).
 

Tonyr1084

Joined Sep 24, 2015
9,744
This ISN'T where the problem is. From your earlier statements you spoke of how everything works fine when you ground pin 85 of KR1. But when you shut the tractor down the high beams come on and stay on. That's because KR1 is still providing power while KR2 is de-energized. In its de-energized state it defaults to the high beams. If KR1 shuts down the lights will go out.

Below you highlight the MFS turn signal lever. When you pull it back it flashes the high beams, as it should. When the switch is in the neutral position (not pulled back or pushed forward) wire 113 remains de-energized and the high beams do not come on. Pin 56D shows that when you push the switch fully forward or fully back it jumps to pin 56A. So you can flash the high beams (pull back) or turn them on until you switch them off by returning the MFS Turn Signal Lever to the neutral position.
Screenshot 2025-01-11 at 8.27.33 AM.png
The whole problem is not with the high beams, it's with KR1 (as you have said, tested and proven) when properly grounded the lights work as you expect when running. But then they don't shut off when you shut the tractor off. That's because KR1 is still active while grounded. Pin 87 is pushing battery power to pin 30 of KR2. IF KR2 is energized the low beams come on. But when KR2 is de-energized the HIGH beams come on. Like the picture in post 33, the problem is with wire 183. Not that the wire is the problem, it has to do with what's controlling it.

Earlier you said this is a known problem and it's known to be related to the BCM or whatever it is that controls lighting. You're asking for a work-around. Until we have fully diagnosed the problem we can't give you a good answer other than installing a switch on the dash board that grounds pin 85 of KR1. And as mentioned earlier, having a switch means the possibility of forgetting to turn it off and running the battery dead.

So if you want to add another relay to apply ground to wire 183 then the relay you install needs to be connected to a switched source. But then every time you run the tractor the lights will be on. Day or night. There is no easy work-around. If it's the BCM then it needs to be replaced.

You can read or ignore my next post.
 

Tonyr1084

Joined Sep 24, 2015
9,744
A friend had a PCM (Power Control Module) on his car that - in part - controlled the air conditioner compressor. Something in the PCM burned out causing some traces on the board to burn and a transistor blew out. He couldn't get any information on that transistor (if it was a transistor, probably was). So we fixed the traces and installed a heavy duty transistor that would switch power ON to the compressor clutch.

The cost of a new PCM was something like $600. We got a hold of a cheap transistor big enough to handle a heavy load and installed it. The end result was the AC was working again. $600? 67¢? Did we find a cheap work-around? Yeah, we did. But we had to go into the PCM. We don't know if you can go into your controller to fix the problem.

This story comes from 1993.
 

Thread Starter

Toolmakerr

Joined Jan 10, 2025
13
The wire 183 its in the big picture i now marked it for you so you can trace it and it doesn't go anywhere else .The controler is not servicable that means its glued with that black glue for windshields its a nightmare to be open its not impossible but its verry hard .I was thinking to buy a relay "JQC-3F(T73) 5V 10A" it cost 0.50$ and its available in our local electrical shop.
Not sure if its going to work but...
btw. thats that down side from this lights schematic its all in seperate pages i have to cut them and place them together if there was exactly on picture explaining how it works i was going to share.
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d7f3f3a6-ccfa-44c0-b979-f0855f632c7b.png994a80b9-33ad-4637-ab3f-d017cf3dff71.pngc6c22777-cf08-4e44-b59d-953afb93207d.png
viber_image_2025-01-11_11-dsds23-726.PNG
 
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