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Discussion Starter · #1 ·
I have an intermittent problem where error code 3350 appears as the instrument cluster is trying to excite the alternator over the period of half a minute or longer. The service manual describes the fault related to the error code as "terminal 50 (crank input) always on", and "engine cranked for too long, or key switch failure". My key switch seems to be operating correctly, and the tractor engine starts almost immediately, but it can take several seconds to a minute or so to excite the alternator. The weird thing is that if it takes longer than about 30 seconds (+/-) to excite the alternator, the 3350 error code appears even though the engine is running - not cranking. If the alternator excites in less than 30 seconds of run time, the 3350 error code does not appear. Why is this happening? Isn't the state of the alternator / charging voltage unrelated to the cranking circuitry, and doesn't this error code coming on when it does indicate some other kind of problem? My dealer went through the guided troubleshooting procedure for the 3350 code but did not find anything. I am hoping someone here has the experience or the expertise to suggest what it is that is causing the error code and what should be done to resolve it.
 

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Hi UncleMerle and
2485793
...if the tractor is still under warranty I would park it at the dealer and not pick it up until it is satisfactory diagnosed and resolved...if out of warranty I would take a look at the sensor that is sending the message
 

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How are you determining when the alternator is excited (guessing with a voltmeter), and more importantly, does the alternator use a standalone regulator or does the cluster or other controller regulate the alternator field electronically?
 

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Discussion Starter · #4 ·
The tractor is no longer under warranty. There is a digital readout in the instrument cluster that allows me to monitor the charging voltage which is approximately 11 volts at startup, increasing to 14.3 volts once the alternator is properly excited. On occasion, this process only takes a few seconds. At most other times it can take up to a minute or more but there does not seem to be any pattern to the variation. In attempting to answer the question about the alternator, I have to rely on the text of the owner's manual which states,

"After engine start, the engine speed at low idle will start at 950 RPM or above in an attempt to allow the instrument cluster to properly excite the alternator. If the alternator does not start charging after one minute, the instrument cluster will stop trying to excite the alternator and the battery light will remain on. If the battery light remains on after the one-minute timer, the alternator can self-excite by increasing the engine speed to 2300 RPM for a short time."

My initial concern was with the length of time it took to excite the alternator, which seemed to me to be excessive. I also believe it to be the trigger for the 3350 error code. Now my focus is on understanding why that code is appearing every single time it takes longer than 30 seconds to excite the alternator. It doesn't make sense since that code relates to excessive cranking, which is not the case. And I can't operate the tractor until I clear the code, and I can only clear the code by shutting the tractor off and restarting it. This begins the sequence all over again. It's maddening.

The tractor has a new battery. It also has a new alternator that I asked to be installed thinking it might reduce the time it took to start charging. When the tractor goes back to the dealer for follow-up, I will ask specifically about the sensor that is sending the error code.
 
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