2007 Mercury Warning System Help Needed

[arniep]

I have a 2007 Mercury, 2-stroke, 50 HP, ELPTO motor. The warning horn sometimes sounds at a low level when the key is on and continues when the motor is running. When I ground the temperature sensor, it goes off like it is supposed to. Sometimes, the alarm does not start when the key is switched on. Then it sounds like it should when I ground the sensor wire. The horn then remains on at a low level.

One mechanic told me my warning control module was bad and he pointed to the rev limiter. After looking at the wiring diagram, I don't see that the rev limiter has anything to do with the alarm system. Another parts person told me the alarm system worked through the three CDM's.

The parts list on the Mercury site does not specify a warning control module and does not direct me in any direction.

Will someone help me with this? Any reason my alarm intermittently sounds at a low level? If it is the warning system control module where is it?

Thanks! I want to go fishing!

[boats.net]

When buzzer is soundind disconnect temp sensor to see if alarm goes off, if does test temp sensor. Disconnect both oil level sensor to see if alarm goes off, if does test sensors.

[arniep]

Done that

I have checked both sensors and they are both OK. The horn sounds louder when I ground the temp sensor and manually depress the level sensor.

I have searched for a part number of the supposed module by my motor serial number (1B527739) on the Mercury site, and there is no item listed.

Using logic (which gets an old retired engineer into trouble at times), I don't think there is a module. I think the warning system on my motor consists of the two sensors and the horn. This is the reason I think this. My manual says the warning for both conditions is a continuous alarm, not one intermittent and one continuous. The second reason I think this is the fact that I can simulate both warning conditions by grounding out the sensors, simulating their tripping. Why would I need a black box in between the sensors and the horn???

I have two mechanics willing to charge me a couple hundred bucks to replace the module, so I am confused!

I need someone to confirm that there is a module or not.

[capttwb136]

I have a similar problem with a 2003 60 Merc ELPT. My warning buzzer does not sound a test beep when I start the motor. I grounded the tan and blue wire from the temp sensor and the warning buzzer sounded. The manual said the warning module/ignition module/ECM could be at fault. Like you I cannot find those modules at any Merc parts site. It has lead me to believe those functions are in the rev limiter now. What do you think?

[capttwb136]

I have checked both sensors and they are both OK. The horn sounds louder when I ground the temp sensor and manually depress the level sensor.

I have searched for a part number of the supposed module by my motor serial number (1B527739) on the Mercury site, and there is no item listed.

Using logic (which gets an old retired engineer into trouble at times), I don't think there is a module. I think the warning system on my motor consists of the two sensors and the horn. This is the reason I think this. My manual says the warning for both conditions is a continuous alarm, not one intermittent and one continuous. The second reason I think this is the fact that I can simulate both warning conditions by grounding out the sensors, simulating their tripping. Why would I need a black box in between the sensors and the horn???
I have two mechanics willing to charge me a couple hundred bucks to replace the module, so I am confused!

I need someone to confirm that there is a module or not.

As I said in the earlier post, I had a similar problem with my 2003 60HP 2 stroke Merc. No dealer could find the warning module. After writing Mercury Marine customer service, they wrote back that that engine did not have a test beep feature at start up. My serial number is OT 624067. Your engine may not have the test beep either. The Mercury people said the alarm system would warn of a oil or temp problem if the motor had one. So if your motor never had a test beep at start up, you most likely do not have the warning module as you suspect. You can send the Mercury Marine customer service people a email and ask them. Hope this helps.