Tachometer not working correctly

[aburr65]

2015 Honda Goldwing 40th Anniversary
Recently my tachometer has been acting up. It will move from 3000 rpm to 6000 rpm then to zero. This happens after about 10 minutes into a Ride. I am thinking a loose connection somewhere. The manual says the ECM may be bad. Ideas?

The bike was involved in a deer accident in 2016. The front end had to be completely rebuilt, same for my ribs on the left side. LOL! It did not start acting up after the wreck until July 2017. I was riding to NJ from Maryland and got in a heavy downpour. It started acting up then. BUT after a few warm days it appeared to be working properly. Then recently it started acting up again. The manual say to check pin 20 in the 40 pin connector. Before I go that far, I am looking for ideas from those more experienced than me.

[newday777]

It's possible that the connector to the dash is loose from a broken plastic clip and the connector isn't all the way in letting moisture in the pins while riding in the rain as you mentioned and was it a frontal deer strike? That would cause it to go bad in rain riding and heavy moisture ladened ambient air.
Cleaning the connector with electrical contact cleaner, pushing the connector in and out, spray more and repeat, then put a small amount of dielectric grease in the connector. Check the hook catch on the connector is not broken.

[newday777]

If a dealer did the accident repair, they might cover that.

[aburr65]

Well took a look at the connectors behind the instrument cluster. And wouldn't you know, the one one the tach side was loose. As I pulled the cluster 2 of the 3 needed to be unclipped. The tach one fell off as I removed the cluster. Plugged them all in and made sure they were tight. As I look back, I pulled the cluster back in 207 to put new LED Headlights i. It was my mess up. Thanks newday777.
Oh, yes it was a left front deer mash. He crammed me a good one.

[newday777]

Good to hear you found it. Clean the pins if you have it open still.

[aburr65]

After several rides Tach is working like a champ! Good to know I have a great forum to get answers and help if needed.

[newday777]

After several rides Tach is working like a champ! Good to know I have a great forum to get answers and help if needed.

Good. Did you clean the pins when you found it?

[aburr65]

Yes. Pins were cleaned and securely fastened this time.

[newday777]

Yes. Pins were cleaned and securely fastened this time.