Possible bad control module?

[bart98stang]

Greetings all. I hope everyone is having a great weekend. This afternoon I took out my boat with the family and coming back in it started to get really rough out. I hit one big wave and momentarily lost all of my gauges (RPM, speed, volts, temp, fuel). Everything came back except for the temp thinking that a wire fell off inside the dash. Got back to the dock and the engine wouldn't shut off. The key was out of the ignition and the engine was still running. I gave it some choke which the engine finally died. I came home and checked in the dash and on the power head and all wires were secured. I tried to start the engine and noticed the test beep and led didn't sound/light and the starter solenoid didn't click. Looking through the wiring diagram in my manual (which I believe is for a newer model engine) and it seems the only common thing between the temp gauge being out, no test alarm, and the engine from starting is the control module. Is there anything else I should be checking or is the control module the culprit?

The engine is a 1988 Mercury 135 s/n B334019

Thanks!!

 

[jeffersondodson561]

Re: Possible bad control module?

Check the harness on the boat end under the cowl for proper connection.

 

[bart98stang]

Re: Possible bad control module?

Thank you very much. When I got home and parked the boat, checking all connections including the harness was the first thing I did. Everything was tight.

 

[Maxz695]

Re: Possible bad control module?

did you check the battery and connetions maybe it took a tumble." A Big Wave" Something got jolted lose. Lost grond . Is there 12 V in the Battery now? is there 12 V going into the ingnition?

 

[bart98stang]

Re: Possible bad control module?

Thanks Max. The battery connections were tight. All connections on the engine itself and on the helm are tight which is the reason why I asked if the control module took a dump on me. It was one helluva jolt we took.

 

[jeffersondodson561]

Re: Possible bad control module?

My guess is you lost your ground (black wire) at your key switch, here use this and see if it helps.

 

[bart98stang]

Re: Possible bad control module?

Thanks fellas, found the problem. A couple of pins were loose in the wiring harness connector in the helm. Re-pinned it and the engine starter right up. Thank you very much.