Seperate from my previous thread. Can anyone tell me if the diff/lock switch is open or closed when the diff is unlocked.
Diff/lock switch, open or closed?
- Thread starter Plain2000DII
- Start date
The warning light for the Diff Lock light is fed with 12V positive from Fuse 14. There is a connection to the SLABS unit at Junction 0761, and the actual switch itself grounds on closure, so I'd say that the switch is closed when the diff lock is engaged and open when it is disengaged.
There is also a logic pull-up resistor on that line which has a function in the SLABS ECU to give a true high/low logic level signal.
That's my interpretation of the schematics.
RAVE confirms that the switch is grounding the light connection when the lock is engaged.
Peter
There is also a logic pull-up resistor on that line which has a function in the SLABS ECU to give a true high/low logic level signal.
That's my interpretation of the schematics.
RAVE confirms that the switch is grounding the light connection when the lock is engaged.
Peter
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Thank you mr. diesel.. a little more involved then I'd hoped. If the cdl is unlocked and the light remains on, then the "switch" on the cdl must still be closed or "grounded". So, if I pull the connector on the switch then no more ground, no more light, no more TC/ABS/Difflock lights after a restart? The dealo helio is I really only use the cdl when one of the propshafts is out. When the TC is fully functional its pretty damn good at getting me unstuck. No rock crawling here.... Thanx again. dave
The thing to remember is that the light is there for a reason, you won't do your transmission a lot of good if you forget that the cdl is engageg.
Possibly better to fit a switch in the line so you can take the switch out of circuit when needed, but put it back otherwise.
The SLABS ECU disables TC/HDC/ABS if the switch is in circuit and the cdl is engaged.
Peter
Possibly better to fit a switch in the line so you can take the switch out of circuit when needed, but put it back otherwise.
The SLABS ECU disables TC/HDC/ABS if the switch is in circuit and the cdl is engaged.
Peter
JohnB said:
TC/HDC and ABS are disabled when the diff lock is engaged. If you think about it you'll see that the ABS system has to have control over independent wheel rpm through the brakes, and that independence cannot happen with the cdl engaged.
If it cannot control the brakes to each wheel independently then TC and HDC cannot be implemented. Purely a mechanical issue.
Peter
Well, this morning I pulled one of the connectors off the diff/lock switch and viola! No more diff/lock/TC/ABS lights. Plugged it back in and they returned. I left it unplugged for now, looks like I'll be needing a new switch, which is a nigglly little thing to get installed correctly so it works. thanks to all for your patience and assistance.
Peter - this may be what I am looking for - I want to just disable ABS & TC permanently on my D2 when I fit the CDL linkage. Where is the switch you are talking about. If I can just set it permanently closed that will fix my problem and get rid off the dash lights.
Background - I just replaced and overlay harness to get one abs sensor into place - cost me $400. ABS now works but the TC now engages the front left wheel if it goes over a bump. Hubs are fine and I really do not like ABS and TC controlling my vehicle so I would just like to cut them out but without the Christmas tree of lights on the dash.
Background - I just replaced and overlay harness to get one abs sensor into place - cost me $400. ABS now works but the TC now engages the front left wheel if it goes over a bump. Hubs are fine and I really do not like ABS and TC controlling my vehicle so I would just like to cut them out but without the Christmas tree of lights on the dash.
JohnB said:
My TC "seems" to work with the CDL engaged. However when I stop and restart with the CDL in I get the 3 Amigos. I read somewhere there is a wire I can cut to prevent this from happening.
wyomingpat said:
Whatever you do, there will always be a remnant of the ABS system remaining, and I'd not want to guide anyone into removing ABS from a vehicle that always had it as part of its design.
I'd guess that there are probably legal issues involved too, if you had an accident you would not be covered by your insurance, that's how it is over here.
Peter
The Fourth Amigo said:
Are you sure its the three amigos? I made the same interpretive error with my cdl sw. what i really had was the difflock/tc/abs lights which is not the 3 A's. You may have the same me, a bad cdl-difflock switch. fwiw, I've been running around now for months with wire pulled on the xfer case(difflock) and no problems.
I'm pretty sure my CDL switch is working properly. I only have an issue on start up when the CDL is in. I can't remember if it produces 2 or 3 Amigos. When I finish installing my winch today or tomorrow I will test it out.
If you restart the truck with the center diff lock in the locked position, the SLABS ECU illuminates the ABS and ETC warning lamps and inhibits the ETC function (the ABS, EBD and HDC functions are retained, but at degraded performance levels). It is not a fault within the system, that is just how i is programmed. It doesn't do it if the diff was locked when the truck is running.
I believe that later SLABS units are running with a different software update to allow CDL to run. I think it is a replacement unit unless you have access to updating the old one. Microcat probably has the chassis/VIN number ranges.
Peter
Edit:
SRD000070 up to VIN 2A999999
SRD500070 from 3A000000 and 4A000001
Looks like the earlier one is no longer supplied, although a few dealers may hold stock.
Peter
Edit:
SRD000070 up to VIN 2A999999
SRD500070 from 3A000000 and 4A000001
Looks like the earlier one is no longer supplied, although a few dealers may hold stock.
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