Smartcraft SC100 Tach with LCD, bench test

[pilotbrent]

I have a Smartcraft Tach with LCD and I am not 100% sure if the screen is bad. It randomly comes on/off, when it is on I can usually read the LCD screen. There have been times when the information is garbled and unreadable. Does anyone know what pins on the back of the gauge you would use to test the LCD? This would help me determine if the LCD is bad or if I have an issue elsewhere.

Thanks!

 

[Skybolt]

The smart craft stuff is all J1939 a form of CAN bus. all serial data communications. If the rest of your gauges work then its most likely the Tach that is bad. If other gauges don't work then your problem is most likely else where. CAN bus in general is a tough thing to t-shoot online, good luck.

 

[pilotbrent]

Thanks SKybolt. All of my other gauges are in working order as well as the tach portion of the SmartCraft gauge. I was hoping there was a way to energize the LCD screen through the rear pins directly with 12VDC to confirm if the LCD was faulty. There seems to be a shortage of detailed SmartCraft wiring info online. If I could confirm the screen is bad I might go for the MercMonitor as a replacement. But if I start replacing parts unknowingly I might just go back with SmartCraft gauge.

 

[Skybolt]

The LCD screen really can't be "energized", you could turn the back light on but that's only the light and not the screen. The LCD needs data to show anything, when it's powered it's still blank. Some turn black for a second then back to normal, but that doesn't mean it's working correctly.

My friends boat had a similar issue, we added an NMEA 2000 translator interface and switched his gauges to all digital read outs. Yours is digital, but with a pseudo analog movement (servo). Your gauge can be had on ebay fairly cheap.

 

[pilotbrent]

Update:

I went ahead and purchased a MercMonitor Level 1 to replace my SmartCraft Tach w/LCD screen. The LCD screen on the SmartCraft must have been bad because the new MercMonitor powered up just fine and the setup was easy. Install instructions were not included with the MercMonitor and I have two questions. One, what is the benefit of installing the included air temp sensor? and two, do I need to connect the Power harness adapter to constant 12VDC? Does it need constant power for memory like a radio? Everything seems to work fine without it being connected. Thanks!

 

[Skybolt]

... questions. One, what is the benefit of installing the included air temp sensor? and two, do I need to connect the Power harness adapter to constant 12VDC? Does it need constant power for memory like a radio? ...

1) The air sensor is for just that, displaying the air temperature. I believe that unit supports that as an option.

2) one goes to the breaker for that engine and the other the key. if there is only one wire then the breaker should be fine, assuming you turn them off every time.

The settings should be stored into permanent memory that does not need any power backup.

Glad that worked out for you.