Deere 200clc travel speed stuck in high

[Eddie Strobel]

Machine has been only working in high for a few years. Occasionally it would go to slow mode but only 1%of time.
Has a tech out to work on engine throttle and fixed it with new PVC behind seat.

He studied two speed and claims it has hydraulic and electric issue.

Unplugged the three solenoids near hydraulic tank, one of them being the two speed controller. Not only did machine remain in high with unplugged, but wiring was constantly powered despite switch position. I think he said the other two wiring connectors also remained powered when they shouldn't be...don't recall what those two connecters purpose were.


Any advice?

 

[mg2361]

Unplugged the three solenoids near hydraulic tank, one of them being the two speed controller

Maybe the solenoid is stuck mechanically? As far as voltage always there, when the switch is placed into the rabbit position, it grounds terminal B3 in the PVC telling it your commanding high speed. If that wire is shorted to ground the controller may think you are always asking for high speed.
Also when checking voltage at the solenoid, do so by backprobing (carefully). Checking with the connector unplugged gives you open circuit voltage or it could also be a bias voltage which does not have the amperage to activate anything and therefore gives you a false indication of having voltage.

 

[Vetech63]

I got a call on one of these yesterday that is stuck in low. I havent had time to look at it yet...........but MG stand by please!!!! LOL

 

[Eddie Strobel]

MG, not sure if you saw, but I emailed you some more specifics, thinking it might be an easier way for both to communicate.

 

[skyking1]

Eddie it might be easier but then no one else who follows along would get the benefit of his hard work, just saying.

 

[Eddie Strobel]

Skyking, I totally get that. But I don't find this forum as convenient as email, text, etc... Also, I would certainly update here with the solution if found.

For the sake of the community, I will keep communicating via this forum. Thanks

 

[Eddie Strobel]

Update...I was wrong...after the tech replaced the PVC, which fixed the inoperable throttle, it is now stuck in low speed.

With engine running, at the SI solenoid between cab and hydraulic tank, I have 24+ volts at the rear wire going into the SI solenoid. The front wire I presume is ground with the travel selector in high. I am not getting ground. With this connector connected and backprobed, I can provide a ground and the track certainly goes into high, so the good news is there is nothing hydro-mechanical wrong.

For some reason, I am not getting ground. Can any light be shed on pin B3 providing ground from speed selector? Which connection might this be found going into PVC? Furthermore, what wire does the selector switch receive its ground? What I am trying to determine is a way to test the switch.

Also, it seems that there must be some criteria to be met before the computer allows two speed to engage. Any sensors, etc... that I should test?

BTW, now that the new PVC is installed, I am able to enter diagnostics on dash, if that helps any.

Thank you all as always!

 

[mg2361]

I am not getting ground.

Any sensors, etc... that I should test?

The PVC controls the ground to the solenoid. The solenoid receives it's ground when pressure is sensed at the propel pressure sensor, the dig and swing pressure sensor is not sensing pressure (no dig or swing functions activated), both pump delivery pressures are low and either control pressures are high. Any of these pressure sensors can affect travel speed.

Can any light be shed on pin B3 providing ground from speed selector?

B3 does not provide a ground. It is looking for a ground. When the speed switch is pressed a minimal voltage from B3 of the PVC travels through the switch to ground. When the PVC sees this and the other criteria above are met then it activated the speed solenoid.

I am able to enter diagnostics on dash

When in the diagnostic mode a "2" on the left side of the display would be delivery pressure, pump 1. A "3" on the left would be pump 2. A 4"" would be control pressure for pump 1, "5" for pump 2. A small "d" would be the dig and swing pressure. Unfortunately you need MPDr or DrZx to see the propel pilot pressure or the speed switch status. The small "c" would get you a calculated propel pressure from the speed solenoid. If you see that reading change it is usually an indication that the controller is trying to activate the solenoid.

 

[Eddie Strobel]

Update.

Went into diagnostics with engine running. I thought everything checked out except....


In display 2, I am not seeing any change of pump 1 delivery pressure. Regardless of what I operate, it remains at 0.0 . Hopefully that is the fix for two speed and possible feeling of reduced digging power. Any insight of sensor location and diagnostics?

Also, in display 8, have code 10, whatever that means.?

In display E, remains at 0.0, despite using hydraulic thumb? Maybe normal?

 

[Eddie Strobel]

Ohh, not totally sure what you mean by this...
Unfortunately you need MPDr or DrZx to see the propel pilot pressure or the speed switch status. The small "c" would get you a calculated propel pressure from the speed solenoid. If you see that reading change...

I do see a large C in diagnostics and this number changes when driving. MPDr or DrZx???

 

[mg2361]

Any insight of sensor location

Mounted on the main hydraulic pump. Pump 1 would the pump to the right looking in the pump compartment.

It has 3 wires. One a constant 5 volt reference, one for return (ground) and one for the signal which should vary depending on the pressure.

have code 10

Code 10 is Pump 1 pressure sensor malfunction

Ohh, not totally sure what you mean by this...
Unfortunately you need MPDr or DrZx to see the propel pilot pressure or the speed switch status.

MPDr and DrZx are diagnostic programs. MPDr is dealer only (although there are pirated versions out there). When you move the travel levers there is a pressure sensor in the propel pilot circuit. You cannot see that pressure in the monitor, only through the diagnostic software. Same for the two speed switch status.

I do see a large C in diagnostics and this number changes when driving

Ignore this. Just worry about the pressure sensor issue.

In display E, remains at 0.0, despite using hydraulic thumb?

That sensor was not installed on all auxiliary hydraulic applications.

 

[Eddie Strobel]

Thank you for the quick update. Here is more info from my diagnostics 2 hours ago. I found what I thought was the pump 1 and 2 sensors and verified by unplugging them and pump 2 data disappeared on dash monitor. I swapped the wires from each sensor and "pump 2" on dash still registered and pump 1 did not. I determined the middle wire for pump 1 sensor wiring, guessing signal wire, does not appear to have continuity to cab.There is 5 volts and ground with the outer two wires.

I found a large wiring connection from pump sensor area under engine, to chassis wiring. I have continuity from pump 1 signal wire all the way through this connection. What was the gray signal wire becomes red with green stripe.

Assuming red with green stripe doesn't change color at cab/chassis wiring connection behind seat, I found about the only red with green stripe at a blue connector going into PVC. I do not have continuity from this pin, back to wiring below engine.

Does this sound like I am on the right track? Any way I can get wiring schematic for pump 1 sensor wiring to help trace it? What are side effects of no sensor data from pump 1??? No two speed??? Reduced digging performance???

If I haven't already said it, my two speed does work when I provide ground to the two speed solenoid!

 

[mg2361]

You are on the right track. Yes that pressure sensor can effect many things. That is why we need to address that first.

I PM'd you.

 

[Eddie Strobel]

So I tracked it down but don't have it apart or fixed yet. It appears the lack of continuity for the pump pressure sensor is occurring at the chassis harness to cab harness connection. This large square connector is behind the seat by the boom side of the cab, and not real fun to access.

I am guessing the problem occurred when the wiring harness was getting worked on from some fire damage. The tech wanted to put shrink wrap on the melted wires without cutting them to get it on. Without the proper tool, we werent able to get the individual wires out of the connector. I am betting this terminal was damaged or slightly pulled out during this attempt, especially considering it happens to be the corner wire of the connector. If I wiggle it, it makes connection, so it isn't totally broken.

After fixing this, I'll see what else doesn't work.

Thanks

 

[mg2361]

The small "c" would get you a calculated propel pressure from the speed solenoid.

Correction. This statement is incorrect. "c" is reading the propel pilot activation pressure.

 

[KenAl]

FYI. Criteria to get high speed travel. Both Delivery pressure sensors are reading “low” pressure. Both Pump Control pressure sensors are reading “high”. Travel pressure sensor is active. Front pressure sensor is “not” reading.
And Hitachi almost always controls the ground circuit. That’s why there is constant voltage to the speed shift solenoid.

 

[Eddie Strobel]

Thanks all. Have a Deere tech coming eventually to look things over again. I haven't been able to find a reason why the controller won't ground the two speed to engage it.

 

[signature600redtop]

Thanks all. Have a Deere tech coming eventually to look things over again. I haven't been able to find a reason why the controller won't ground the two speed to engage it.

same things is happening with my machine -- do you remember what the final fix was -- pressure sensor on pump 1? wiring to pressure sensor ?

 

[Eddie Strobel]

I thought I posted an update but I believe, in the end, a new controller behind the seat was required. I know it was a head scratcher and eventually involved a Deere mechanic to struggle through it. I think he tried a spare controller before ordering one, or something.