Auto Throttle is giving me fits. New to me 1997 model Serial# 4NR0----- with 3900 hours. I've had it 2 weeks and haven't had time to get service and parts manuals for it. When I bought it, The auto idle down didn't work. The right joystick switch would idle it down when pushed. When the hydraulic movement is sensed the RPM goes to the setting like it should. One day last week, it wouldn't shut off with the key, we used the switch behind the right armrest to enter manual mode. This went on for a few days. Now it won't work in manual mode, climbing out and shutting it off at the injection pump by hand. 2 days ago I couldn't adjust the RPMS anymore only just wide open. I took the throttle servo assembly out and put it on the bench. Opened it up. Gears are all fine, motor turns and moves the cables when power is applied. It didn't look or smell like burned electrical. Any suggestions would be welcome. Thanks, Greg
This morning while warming up the throttle worked with the dial for a couple of minutes then quit.
There are several issues that could cause this. You do need to get some information out of the computer to troubleshoot it though. Maybe someone here could describe how to get into the diagnostics of the computer and then decipher any fault codes that might be there. You should check the wiring connections on the governor throttle motor and the wiring harnesses at the engine. A loose connection could explain it. Good Luck!
Bite the bullet and order a new throttle control, the PC board is the trouble, I just put a new one in my 325B and the cost was 1200 bucks....good luck.
I've bit a lot of bullets this year! How did you determine the PC board was bad? Also, the connections at the throttle control look good. Will check more connections!
I sent you an email.
Per sent instructions to access the service and error codes. I need to go back and access the error log for stored codes. Here are the codes for today: This code came up early (while the throttle was working: 4302 (Data Mismatch 2 between alternator and speed sensor- speed sensor is abnormal) This additional code came after the throttle failed: 2303 (Governor actuator does not move) When I start the machine, the throttle control works for about 1/2 an hour. Though the key will not shut it off at anytime. The throttle will stop functioning at whatever speed it's set at. Cooled off at lunch, the control works again until it warms up again. I have a parts book coming, I don't know where the speed sensor is.
It kind of sounds like two problems. Did you check to see that the cables that move the throttle are not frozen? Speed sensors are pretty common to go out also. I don't think I would just buy a board for the thing until you eliminate everything else. Sounds like you are going down the right path. Good Luck!
John: I took the throttle control out and inspected the gears and the motor in the servo everything worked on the bench My guess at this point is wiring in the engine bay. Need to find where the speed sensor is/ what it does Thanks, Greg
Speedsnsor is mounted on the bellhousing reading the flywheel
Well as live in the sticks here a service call run's about $500 bucks just to get them here. I call the cat mechanic I normally use and he said if you want to try his educated guess he said replace the board....took his advice, replace the throttle control and basiclly put the 500 bucks back in my pocket.....could have went the other way to but he's a 30 yr mechanic on cat...so I took the risk and it payed off for me., not sayn you'd be as lucky...lool
Have you calibrated the controller. Whenever it is removed it should be re calibrated. Calibrating is also a good troubleshooting procedure. If it fails calibration it will give a code and a reason why. Performing the sweep test is a good way to hear how its working. see if its smooth or jerky. All can be done through the monitor panel.
I don't have a service or parts manual...yet! I got the following codes off the error memory log today: 2201 (governor actuator feedback sensor circuit is open shorted to battery) 2303 ( governor actuator does not move) 420C (electric power supply is too low) A203 (Communication is abnormal in the controller) I cleared the log and got these codes at the end of the day: 2303 420C I will check into the voltage issue, I did check it at the cig. lighter and it was 27 volts when running. I did get the info from the dealer on how to calibrate the governor controller. I'll try that tomorrow. Couple more questions/observations: The first symptom was the inability of the key to shut down the engine. When the controller is working (first 1/2 hour of operation), the key will not shut it down. The fault code 4302 (from yesterday) saying the speed sensor is abnormal, would a bad speed sensor cause the controller to dork out? Gotta love electricity! Thanks for the input! Greg
Speed sensors in the bellhousing are prone to fouling. They are magnets and worn off pieces from the starter and ring gear will stick to it giving false readings. Just unplug the sensor and unscrew it and clean it, check the ohms, should be 110-280. If ok screw back in until it touches the flywheel then back it off 1/2 to 3/4 turn. When operator selects an engine speed by placing the engine speed dial in one of the ten positions. The controller will determine if the engine is operating at the speed that was selected by comparing the engine speed with the engine speed sensor. If the engine is not operating at the selected speed the controller activates the governor actuator which moves the governor lever. The controller uses the governor feedback sensor to place the governor lever in a position that corresponds to the selected engine speed. The governor actuator uses a cable(s) to rotate the pulley. If the pulley is rotated counterclockwise, the governor lever that is connected to the pulley will move in the accelerate direction. If the pulley is rotated clockwise, the governor lever will move in the decelerate direction. Does the speed dial change the numbers on the monitor panel? are they correct in all positions? 1=1 etc.
The speed sensor will cause you a few different head aches. Lee-online has it right in explaining what to check. I saw you checked the motor itself but did you check the cables that wrap around the pulley. I have seen the cables freeze in their housing causing the motor to pull too many amps and set the fault codes. Good Luck
When the throttle dial is turned, the numbers on the screen change from 1-10. In the morning, the throttle moves but it probably is out of calibration since I took it out and checked it. But I can move it from low to high. Until it quits. Any ideas on the initial problem of the key not shutting it down? I'll clean and check the speed sensor tomorrow. John C: The cables are free and correct, the gears in the drive are good and the DC motor turns. Everything physically looks good in the controller.
Speed sensor is bad, ordered another! Can't calibrate the governor w/o it. I'll post back with results.
Speed sensor installed, the throttle and the AEC works now! Could NOT get thru the governor calibration....it would hang at 70 07. Still won't shut down with the key, but switch over to manual and shut down there.
70 07 is collecting data from the speed dial. how long have you waited for the calibration to finish? do you get any error codes?
This AM I tried to calibrate again. It hangs at 70 07. I gave it 3 minutes at that # and stopped the process. After an hour of use, the controller quit working today (after working for 2 days) So, I'm back to square one....running wide open and climbing out to stop the engine. Codes: 2303 420A 420C
In my last post I said the controller stopped working....I meant governor actuator! The service manuals arrived Saturday:Banghead So now maybe I can go at this more intelligently...if I can find it in the manual. I've found the procedure to check the speed dial (on right console) But couldn't find any info on testing the Key Switch.....is it buried in the manual somewhere? There is a Timer associated with the key switch, but I couldn't find any info on that either?
Aren't your machine a bit too old to have the timer and shutoff solenoid?
I thought I read that there is a timer. Maybe in the starter system manual? I didn't see any reference to a fuel solenoid. Checked the ground at the actuator and form some resistance. Used contact cleaner and reconnected and the resistance was gone. But the actuator works for 2-3 hour each morning...until the engine compartment and frame get good and warm, then it stops. Tomorrow AM it will work again.
My muffler melted my throttle cable, 1600 bucks later...shes as good as new,
Is you actuator mounted underneath the back engine mount like mine? What did you do with your old actuator? My cables are fine, everything works at the start of the day. Then the throttle quits moving after about an hour. Too busy working with it to stop and work on it. Going to freeze one of these days! Thanks! Greg
yes it is, it was actually the guy before me that had the problem, he rigged up a cable to inside the cab for a manual throttle. But the engine cavity was filled with black soot. ----> new muffler.
Biting the Bullet! I'm getting closer to "biting the bullet" and replacing the governor actuator as Grandpa said! Does anyone else sell this part? Cat's price: $1008.
I sat back and watched this thread....you reacted along the same line's I did. I hated to spend that kinda money on something like that, so now my question to you....wouldnt you rather have a manuel throttle? Our problems would have been fixed the same day we encountered them. And all operators usually run WOT anyways so where's the benifit? But I just have to say this, "I told you so"!! bah ha h ha I sound just like my ol man...lol Take Care Boiled Owl.
How do you calibrate the controller? Having throttle issues with my 320B, going to clean the speed sensor tomorrow
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Does this machine have the 4 setting capable auxiliary hydraulic system (for ho-pacs, hammers, and shears)? There will be a control box with LED numerals and 4 soft touch buttons, right near the air cleaner housing. If it does, I've changed at least 15 on my 322b and 330bs. It can be bypassed under the cab floor, to get back to the throttle not being intercepted by the controller, but the connectors are a PITA to access. They (the $700 auxiliary controller) can give the machine a multitude of different throttle and powershift issues, even when auxiliaries are not in use, including governor calibrate. If you're not using auxiliaries, it can be left offline.
hi Per can you tel me how access the service codes on 320B thanks in advance
Hey guys, I am having some issues with auto governor inop on my Cat 312 and also a dead computer on a Cat 311. Would appreciate if someone can send me the fault code diagnostic process and also the stepper recalibration instructions and finally.............how much is a Cat 311 computer? I could only find a 320 computer at the moment. does anyone know if this is compatible? thanks in advance
Hey guys FOund my problems........ 312: The auto idle button on the right hand side lever was stuck down. So released this and problem solved on the 312 and it worked like a charm afte that 311: Computer power supply was broken somewhere. havent traced exactly where but just bypassed the pin and gave it a direct supply from the key through a fuse. So its back up and running now! Thanks Nige for the wiring diagrams.......helped us out a treat! If anyone has the instructions for calibrating the stepper on a 312 BL please let me know as i had these but they are lost. I also have a 312 service manual so if anyone wants any particular info from it please pm me.
Had a similar problem. Bought a new governor actuator and was calibrating. At first it didn't enter calibration cos it was showing 70 HF 02 (speed sensor is abnormal). I checked engine magnetic pickup speed sensor and found the resistance is zero Ohm. had to get another that read 180 0hm and fixed. the fault cleared and I started the calibration again. my problem now is that it reached 5 and stopped, tried again for like five times same thing with no any error code. Can anyone help me on what I could be missing? Please it's my first time. Thanks.