CAT 246C Joystick

[Fairfieldcounty]

I have a CAT 246C that is presenting with a low speed condition that appears to be caused by the joystick. The machine will only move at about half speed ginghams forward until the joystick is brought back to neutral and then it will run at normal operating speeds when pushed forward again.

Could this be a bad sensor or something else before I dump an $800 joystick into it? Any way to check the joystick?

S/N : JAY08135

 

[Vetech63]

Any fault codes?

 

[Fairfieldcounty]

Yes:

E875-1
E875-2
E875-3
E570-2
E360-2

4420047


70-3
1251-4
2471-3

 

[kshansen]

Hope someone can confirm or correct me if wrong, been a few years since I touched a Cat machine, but I'm thinking that if the codes do not have the words "SERV CODE" after them they are not active but stored codes.

So my first question would be do any or all the listed codes show "SERV CODE" after them?

I know I had a list of all Cat Error codes saved at one time but not finding them right now!

 

[Nige]

E360-2 - low engine oil pressure.
E570-2 - unexpected right travel motor forward speed detected.
E875 (1, 2, or 3) - Low system voltage.

70-3 - Parking Brake Switch
1251-4 - low system voltage w/engine running
2471-3 - Door Switch

Parking brake switch and door switch can directly affect machine movement, especially if either of them is a fault that comes & goes.
However with so many different codes for low system voltage I would suggest checking the charging system first. machines with a large quantity of electronics can get quite sensitive to a voltage that is below normal.

 

[Per Eriksson]

I'd go for the travel motor speed sensor code, when that happens the computer restricts the speed to protect the machine.

 

[Fairfieldcounty]

I believe the low voltage codes to be stored codes. we had an issue with alternator at one point over the summer. This machine eats alternator belts, I know a couple guys with the same model that all have the same issue since new. we keep 2 extra belts in the machine as a just in case

Joystick appears to be registering, I ran it with the screen up that shows the % of x/y axis and it all appears to be on par, even though I would never be able to tell accurately.

 

[Fairfieldcounty]

Looks like there's 2 speed sensors, which one do I take a run at?
262-3764 and 191-8303 (looks like a motor speed sensor)

 

[Nige]

262-3764 is the speed sensor for the drive motor. In fact it is two sensors in one housing, with a common power supply & ground from the ECM and a signal wire to the ECM from each of the two sensors.

There have been many cases where owners have replaced speed sensors and the fault remains - usually because there was a wiring harness fault between the speed sensor and the ECM. If you want to go into the wiring before shelling out for a new sensor you'll need an electrical schematic.

 

[Fairfieldcounty]

I replaced the sensor in the wheel motor on the right side. no change in fact worse. It is now an all the time problem. I have more codes now along with exclamation inside diamond on, as well as exclamation inside the lightbulb looking symbol.

91-3
70-3
these are on the first screen and appear to be active codes. thoughts?

 

[Tyler d4c]

A bad throttle position sensor is normally what causes the half speed with the control in my experiences id get the active codes repaired replace the tps and calibrate everything and go from There. You with need et to do the calibrations

 

[Fairfieldcounty]

A bad throttle position sensor is normally what causes the half speed with the control in my experiences id get the active codes repaired replace the tps and calibrate everything and go from There. You with need et to do the calibrations

do I need et to calibrate the wheel speed sensor? I had wheel speed sensor codes previously. im throwing the alert for air filter alert now along with 91-3 and 70-3. nt sure what the are. can't find them anywhere.

 

[Nige]

I replaced the sensor in the wheel motor on the right side. no change in fact worse. It is now an all the time problem. I have more codes now along with exclamation inside diamond on, as well as exclamation inside the lightbulb looking symbol.

I did mention before that simply replacing the wheel speed sensor without carrying out the troubleshooting procedure for the Diagnostic Code might not necessarily yield the desired results.

 

[Nige]

It is now an all the time problem. I have more codes now along with exclamation inside diamond on, as well as exclamation inside the lightbulb looking symbol.

91-3
70-3
these are on the first screen and appear to be active codes. thoughts?

Here are the Diagnostic Procedures for the two Codes. I'll send you the Electrical Schematic separately.

 

[Tyler d4c]

do I need et to calibrate the wheel speed sensor? I had wheel speed sensor codes previously. im throwing the alert for air filter alert now along with 91-3 and 70-3. nt sure what the are. can't find them anywhere.

Yes any time a part of that system is replaced it needs calibrated

 

[catman13]

i would send it cat and have them plug into and clear or diagnose it and stop guessing and buying unneeded parts, i have a 289c the hydraulic joystick went bad i just had them pick it up [ cheaper than bunch of service calls ] find the problem and tell me what was wrong , had them put joystick in then calibrate it, not cheap but down time aint cheap either

 

[Nige]

Yes any time a part of that system is replaced it needs calibrated

I am of the opinion that you don't need ET to calibrate the replacement motor speed sensor. Replacing a TPS is a different matter, the replacement sensor requires calibration.

However, the machine does need to move in order to change the Active Diagnostic Code to a Logged Diagnostic Code so that it can be cleared from the machine memory. See below which is from the Troubleshooting procedure for a motor speed sensor fault. The bold type is NOT mine, the manual has it like that to stress the need to move the machine in order to change the Code from Active to Logged..........

"If this diagnostic code is active, the ECM will keep the code active until a good sensor signal is observed by the ECM. This means that the drive motors must be moved in order for the ECM to determine that a good signal is present and to change the Code status from Active to Logged."

 

[Tyler d4c]

I am of the opinion that you don't need ET to calibrate the replacement motor speed sensor.

Thats good if not needed ones ive worked on i ran though and calibrated it tho.

 

[Fairfieldcounty]

Did some digging and have the cab back up because I need to do a hydraulic line and the plug for the pedal (assuming this is the TPS) was loose. I’ve plugged it back in and secured it. The code for the wheel speed sensor is now showing as logged I believe because it has the floppy disk symbol behind it and is screen 2. I’m gonna be dropping the cab tomorrow after i do the hydraulic line and see how it turns out