REPOST Enforcement Mod
Join Date: Feb 2006
Location: Wesley Chapel, FL
The ECU is a solid-state computer. There's nothing in it that will "click". You're likely referring to the relay box. In the older models, the ECU and relay box are co-located in the tail. The ECU is thin and has 2 long connectors attached. The relay box is smalled and has 3 connectors to it. The relay box contains, well, relays of course. A relay is a remotely operated switch and they click all the time when activated. They should not repeatedly click back and forth though.
The relay box contains the relays for the ECU, the fuel pump, starter, cooling fan, and headlight. One of those is getting an undervolt condition when activated which is causing it to disconnect. It tries to hook up and disconnects again. That's the clicking you're hearing/feeling. But it isn't the ECU.
Take the relay box away from the ECU and troubleshoot which relay is not working. It's likely the fuel pump relay which is the only one that should activate when the ignition switch is on. The others need other things pressed to activate (starter button, headlight switch, fan, etc). Based on the age of that bike, it may be a connection issue with the wiring. Or it could be just a crappy battery. You said it's new, but what kind is it? If you just bought a cheap Wally-world "motorsports" battery that doesn't have the proper rated current for that bike, a clicking you will go. Need to troubleshoot the issue more, but hopefully that helps to figure out where to start.
I may not be perfect, but at least I don't ride a Suzuki.
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