140a rev light on gauge at very low rpm

[woody7]

hey guys i was recently trolling with engine(DF140a) just in gear (very low rpm) and i got a beep and noticed rev light was lit up on gauge continued for 5 mins or so an beeped again...took revs up to maybe 1500-2000 and light went out....i have been googling and have found similar suituation if you have troll mode switch fitted which i dont....so is it the motor just thinking its in troll mode???
thanks for any info

[Murray]

As far as I know the Rev. Limit light should only come on when your first power up the ignition switch(self check) and if your in an over rev. situation. You are in neither situation. Your 100% sure it was the Over Rev. indicator?

[woody7]

yes murray 100% rev light...ive done some research and it looks like a is behaving like its in Troll Mode..although .i do not have the troll mode switch installed....

[Murray]

Weak battery, sending weird signals to the ECM? An Over Rev. warning on low PRM doesn’t make sense, perhap someone with more knowledge will chine in. Sorry I can’t be more help.

[Greg Moore]

Weak battery certainly a possible cause. They don't have very big alternators and the output is drastically reduced at idle. Did you have much running electrically? You may have been drawing more than charging and battery voltage dropping critically low.

[woody7]

Thanks for reply’s.....Battery not really a possibility as I have 2 optima batteries(that are in excellent condition) that are more than ample to supply electronics I had running...I was trolling after a 65km run to the spot at high speed so batteries would be in excellent condition..have spoke to suzuki and they have confirmed for some reason the troll mode of s being triggered electrically..so I need to turn everything off and turn equipment on until I find what triggers it..

[dlnw98]

I had the exact same thing happen on my DF140a last summer. I do not have the troll switch installed either.

It was entering the troll mode immediately after start somehow.. Just like yours, if I would advance the throttle it would exit the troll mode and run fine.

It appeared to be something in the wiring harness under the dash causing it. There is a plug in the harness for the troll switch installation. With that plug unused, all I can guess is that somehow something bumped the pins in the plug to activate the troll mode.

I repositioned and re zip-tied the harness under the dash to secure it. I have not had the problem since...

[woody7]

Yes that makes sense as I was rummaging around in there a few weeks ago...I know the bundle of wires you are talking about...so I’m looking for a plug with nothing plugged into it?how many wires does the plug have(colour of plug)
thanks heaps mate I think you may of hit the nail on the head..

[Greg Moore]

Best check that on mine then, I run a 140a as well..

[woody7]

Have you also had this issue Greg?

[dlnw98]

Unfortunately, our boat is buried deep in a shed navigating a Minnesota winter. I don't remember what the plug looks like. If you google Suzuki Troll Switch, somewhere you will find the installation instructions for the switch that can be referenced. If memory serves, it was the only vacant plug in the harness. I moved it clear away from anything else and secured it with Zip-Ties. Knock on wood, no recurrence since then.

[woody7]

well went out today and problem seems to have been fixed..Thanks dinw98 for the pointer...i rearranged the wires you talked about and found a blue wire with a male bullet connector ...i covered the connector in tape hoping to resolve the issue by doing so and hey presto it seems to have worked....only explanation i have for this is there is a bare wire ground wire in that bundle of wires and maybe it was making contact with the exposed male bullet connector...fingers crossed its fixed

[shallowaterhunter]

I have a 2007 DF140 and my service manual calls for lead acid battery. I bought the boat with an Optima Blue Top as the cranking battery and was getting false alarms, changed to a lead acid and alarms went away. Check your service manual and see if it recommends a lead acid battery.

[woody7]

I have a 2007 DF140 and my service manual calls for lead acid battery. I bought the boat with an Optima Blue Top as the cranking battery and was getting false alarms, changed to a lead acid and alarms went away. Check your service manual and see if it recommends a lead acid battery.

can you recall which codes you were getting?

[Benbeer]

I am having a rev limit light problem on my 25ft JC Pontoon With 140HP Suzuki 4-stroke. Marina not helping me out since I winterized it elsewhere this year.