Ducati Monster Forum

Moto Board => Tech => Topic started by: Pat S67 on September 07, 2013, 05:52:57 PM

Title: Tacho killing engine when signal connected
Post by: Pat S67 on September 07, 2013, 05:52:57 PM
Hi Guys,

I picked up a cluster from a 2001 M900 Carb'd to refit to a 1995 M400, checked through the wiring diagrams, and apart from a few of the idiot lights not supported, supplying a ground to the Neutral light, and adding the "Signal" through the J pin of the pig tail instead of the side stand switch, all was going well.

Problem: As soon as the signal (tapped from the middle connector on the right igniter) is connected the engine starts firing on only one cylinder, and will die shortly after. I tested the tacho on my 2001 M600 (came standard with a tacho) and it behaves exactly the same. First assumption is the "new" tacho is a dud.

Would a failed tacho do this, or is this tacho simply not suitable for the M400/M600

(http://farm4.staticflickr.com/3706/9697792406_b1d37645e9_z.jpg) (https://www.flickr.com/photos/91610734@N06/9697792406/)

Rear of the M900 tacho

(http://farm4.staticflickr.com/3760/9697802012_aa20c0c683_z.jpg) (https://www.flickr.com/photos/91610734@N06/9697802012/)

Front of the M900 tacho

(http://farm4.staticflickr.com/3818/9697793132_383c5a589d_z.jpg) (https://www.flickr.com/photos/91610734@N06/9697793132/)

Rear of the working tacho from the M600

(http://farm8.staticflickr.com/7283/9694558883_e7abd5e907_z.jpg) (https://www.flickr.com/photos/91610734@N06/9694558883/)

Label on the working tacho from the M600 there's nothing on the M900 tach except for a brown dot sticker if that is significant.

(http://farm8.staticflickr.com/7307/9697838586_3e86e16ed4_z.jpg) (https://www.flickr.com/photos/91610734@N06/9697838586/)

Point where I am taking the tacho signal from (centre connector)

TIA Pat
Title: Re: Tacho killing engine when signal connected
Post by: Speeddog on September 07, 2013, 06:57:16 PM
A 2001 M900 would be injected, not carbureted.

Possibly the tacho is different on the injected bikes.

Title: Re: Tacho killing engine when signal connected
Post by: Pat S67 on September 07, 2013, 08:39:59 PM
Thanks speeddog, could well be different. Checked the listing from the seller, they only quoted it as being from a 2001 M900.
Title: Re: Tacho killing engine when signal connected
Post by: Pat S67 on September 07, 2013, 08:59:16 PM
Found a generic 2001 monster manual, and sure enough there is 2 wiring diagrams, one for injected and one for carb'd.
The injected diagram shows the tacho signal coming direct from pin 3 on the ECU.