TC29D Hour Meter

[Lloydthumper]

I know this post is old but I am new to the forum and also new to owning a Newholland Tc45 and the tach and the hour meter is not working. I have been searching for days now and reading many post concerning the tach and hour meter not working. I have ohm'd out the tach and the hour meter and both check good. I have checked the signal from the alternator with just a fluke meter and it reads 2.6volts on AC and 7.6 volts on DC but a lot of what I have read says I shouldn't be able to check it with a meter unless it measures frequency. Has anyone solved this problem without buying that ridiculously priced gauge cluster? any help would be greatly appreciated. Thanks Lloyd

 

[Spicer]

I know this post is old but I am new to the forum and also new to owning a Newholland Tc45 and the tach and the hour meter is not working. I have been searching for days now and reading many post concerning the tach and hour meter not working. I have ohm'd out the tach and the hour meter and both check good. I have checked the signal from the alternator with just a fluke meter and it reads 2.6volts on AC and 7.6 volts on DC but a lot of what I have read says I shouldn't be able to check it with a meter unless it measures frequency. Has anyone solved this problem without buying that ridiculously priced gauge cluster? any help would be greatly appreciated. Thanks Lloyd

Your tach and hour meter rely on a functioning alternator. The first step is to measure the output voltage at the alternator when running. The Voltage should be between 13.8 and 14.5.

Mike

 

[Lloydthumper]

Your tach and hour meter rely on a functioning alternator. The first step is to measure the output voltage at the alternator when running. The Voltage should be between 13.8 and 14.5.

Mike

I checked the voltage coming off the altenator when running it is putting out 14.3volts.

 

[Spicer]

Check for 12V power at the cluster:
With the ignition "on" engine "off" is the oil pressure indicator lit?
Check the ground connection to the cluster with an ohm meter. It should be less than 1.5ohms

Check the Alternator signal wire:
With the ignition "off" measure the ohms from the "Signal" connection on the alternator to the cluster(the wire color will be the same). It should be less than 1.5ohms

Microprocessor:
The hour meter, Tach and temperature gage are the only components controlled by the microprocessor. Run the tractor until it reaches operating temperature and check if the temperature gage is operating.

Mike

 

[Lloydthumper]

Check for 12V power at the cluster:

Check the Alternator signal wire:
With the ignition "off" measure the ohms from the "Signal" connection on the alternator to the cluster(the wire color will be the same). It should be less than 1.5ohms

Microprocessor:
The hour meter, Tach and temperature gage are the only components controlled by the microprocessor. Run the tractor until it reaches operating temperature and check if the temperature gage is operating.

Mike

With the ignition "on" engine "off" is the oil pressure indicator lit?
Check the ground connection to the cluster with an ohm meter. It should be less than 1.5ohms

Everything you listed checks good 13volts to the cluster. Ground is good at .2 ohms. The pink signal wire coming from the alternator read .3 ohms. The oil pressure indicator is not lit. With the switch off. My tractor is a tc45s not the D model it doesn't have a temp gauge I've looked at the micro processor inside the cluster and it appears to be an eprom which if so I dont under stand what they would have needed a program to do in operation of the gauges. All the capacitors check good when removed from the board as well as the resistors the processor is the last thing I know it could be but before spending alot on a gauge cluster It scares me when others have had the same exact symptoms and replaced the cluster and it still doesn't work. Theres no reason for that cluster to cost so much. Thanks Lloyd

 

[MikePA]

Has anyone solved this problem without buying that ridiculously priced gauge cluster? any help would be greatly appreciated. Thanks Lloyd

Theres no reason for that cluster to cost so much. Thanks Lloyd

Lloyd, no offense meant, and to state the obvious, but since you've mentioned this twice, it's not unusual for items to be priced higher than the cost of the parts they're made of. Add to this the fact the TC45 is an older model, and the cost goes up. The same thing happens with vehicles. The cluster for my TC25D is $684 for a reman and $789 for a new one.

I'd call Messicks about this problem, tell them what you've checked and see if they think a new cluster will fix the problem. Also ask them if it's OK to return the cluster if it doesn't.

 

[Spicer]

Lloyd,

Just to clarify, was the oil lamp lit when the ignition was "on" and the engine "off"?

The tach signal is connected directly to one of the stator leads inside the alternator. This provides the rpm dependent AC signal for the cluster. You were not able to test this signal, but if the alternator is functioning normally there must be an AC signal present at this connection.

The microprocessor function:
1. Increment the hour meter every 36 seconds when there is a tach signal present.
2. Bias the two winding on the tach and temp indicators. The gages are setup in a differential circuit; one winding pulls the needle up and the other down.

I think you have exhausted all possibilities.

 

[Spicer]

Lloyd,
Hold off purchasing a new cluster.
2.6Vac is too low. I will check my tractors tach signal as soon as I can.
I apologize for missing that.

Mike

 

[Spicer]

Lloyd,
Below is the scope pattern from my TC40D at 1500RPM
F: 248.9Hz (1500rpm/60sec x 10) = 250hz
Vk: 7.444V (Volts rms)
Vp: 16.40V (Volts peak to peak)

2.6Vac is less than half as it should at 14.3Vdc. You should really have some one look at this with a scope.

Mike