having trouble locating the proximity switch

Hello All thanks for all your help We were able to get this fixed!
Was able to get a schematic found there was an extra wire add to the black wire on the 90 degree proxy sensor, I removed that wire and unit works as should.

Thanks again!

Hi
Per below, if you still need support, you can complete a quick technical support form at the bottom of the main combilift.com web site or direct link https://warranty.combilift.net/technical-support-form/. The form only asks for the minimal info so the team can quickly help you. There is no login required and no charge for this support.
Combilift has Technical support technicians across the world including in NC at the North America Headquarters, that can help.
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BLey I found this morning that one of the wires were pulled out of the relay. i fix and repaired it. Now the front tires are over rotating passed 90 degrees. the 6 way valve never turns off.

thanks for your help!!

Definitly should be running a plc board in the dash.

I was re reading your earlier responses and need clarification. When you said you checked the rear prox switches and both lights are on what do you mean. Only one prox switch on the rear should be lit up at a time.

And when your checking them are you turning the rear tire all the way to the 90 position touching the stop bolt to the frame, checking to see if it is being turned on and that the air gap is no larger then 8mm. (As well as checking to make sure the other 0 degree prox switch is Off)?

But if your correct and saying everything is good with the rear prox switches i would

Check relay 9 terminal 30 for 12v. If it has 12v jump to terminal 87 to bypass the relay and see if the change over valve (6port) operates.

If it doesnt its wiring or connector issue.

If it does operate check relay 9 terminals 85 and 86. One should have ground and the other should have 12v after the plc board has recieved a signal from the rear 90 prox switch and the directional lever is in the right or left position.

Bley, Engine is 3.0L PIS(GM) Date 10/2016

What engine and date of manufacture. Relay or PLC truck.

Newer PLC trucks relay 9 controls the 6 port change over valve.

Power to pin 30 on relay 9 come from F4 20amp.
Pin 87 goes to the coil on 6port valve.
PLC board applys power to relay 9s coil either on 85 or 86. Cant remember. And the other is grounded. After it recieves the signal from the rear 90 prox.

If you have the owners manual for the unit I suggest you run through the PLC diag as its easy to confirm if the PLC can output and turn on the valve as well as confirm that its getting the signal from the prox switch.

does any one have a wire diagram that shows where the changeover valve gets its power from would be very helpful. I can add power after the rear tire stops moving and add 12v to the changeover valve and the wheels will move.

Thanks!

Thanks,
I have swapped the rear proxy sensors with and other working unit that unit still works fine. and all relays test good.

Hi,
The proxy sensors unfortunately do get impacted and as they are needed to control the movement to the alternative directional change, a loose or impacted one should always be checked for. When a truck ships new a spare one is provided in the cabin.
If I understand correctly when you put the directional level to right, the rear wheel turns to 90, (parallel with back plate), but the front wheels do not turn to 90 also. If this is the case then first check the rear wheel 90 proxy sensor has been activated. (When it activates it changes the oil supply in the 6 port to turn the front wheels to 90, until the front wheels reach the 90 proxy, then the cycle is complete.)

If you still need support, you can complete a quick technical support form at the bottom of the main combilift.com web site or direct link https://warranty.combilift.net/technical-support-form/. The form only asks for the minimal info so the team can quickly help you. There is no login required and no charge for this support.
Combilift has Technical support technicians across the world including in NC at the North America Headquarters, that can help.
You can also request access to our knowledgebase where you will find more information available. Hope you get sorted.

Then try swapping some relays under the dashboard

Light comes on , on both proximity switch when tire stops moving.

Check the proximity switch on the rear tyre is being seen when the rear tyre stops moving.