01 SAN Check engine light

[treverspence]

I have an 01 SAN with the GT40. Can a bad alternator make the check engine light come on? The mechanic who is working on my boat seems to think light being on is caused by a bad alternator, however it is putting off 13 volts. If not what should I check to make this issue go away oil pressure and temp look good according to the gauges.

[WakeSlayer]

What is putting off 13V ? Did you check at the battery terminals? While running? Or are you just going by the gauge. Alt should charge at 14+ Mine is currently charging at 14.3. Have him check the sensors, too.

[DanielC]

If the check engine light is on, there should also be a trouble code stored.

[treverspence]

More info Help please!

So I had all three sensors replaced 2 oil and one temp light still on any more ideas. Does computer need to be reset if so how, is there anything else that can cause such as low voltage mechanic says alternator is only putting out just over 12 volts not sure where he is getting this reading as I could only speak with his wife/ secretary today. Just had exhaust manifolds & risers replaced could this cause issue?

[treverspence]

Anyone have any ideas?

[crobi2]

It's interesting, I have a 2000 SAN with the GT40 and threw the alternator belt one day while out riding. Check engine light did not come on (it does work) and my voltmeter has been moved down to the right panel below the throttle so I never noticed that my volts were going down. Fortunately, I noticed the belt down in the bilge when I was bedding down the boat for the evening.

Anyway, I guess my point is my check engine light did not come on even though the alternator was producing 0 volts.

If my boat is not messed up then your problem may not be the alternator.

[AirTool]

The check engine light generally reports emission/ignition/engine faults.

My 93 chevy truck does have a "check gages" light which is nice.