I need some help. A friend asked me to look at his boat since the repair shop he usually goes to is booked out for weeks. I thought this would be pretty simple.
Sorry, I didn't think to write down the complete motor model and serial number but the boat is 2002 with 5.0GXi. I was hoping to get some suggestions of things to check before I go down there again- I'll get the complete numbers then.
He was at no wake speed and the audible alarm started. It's "beep beep", maybe a bit longer than it takes to say it out loud. Then quiet for a bit longer than the time of the beeps and then repeat... forever. All his gauges showed normal so he idled back to his slip. I went down the next day and it does it from a cold start and never stops.
At start, everything seems normal- the alarm gives two test beeps when the key is turned. Then nothing until the motor starts and immediately the beeping starts. I removed the wires to the exhaust risers and the oil pressure switch (spade connector, port, aft, over original oil filter location). I first disconnected one at a time and then all of them. I waited for over a minute. There's plenty of oil and the gauge shows pressure. Nothing felt unusually hot and the temp gauge shows normal and yet it continues to beep.
I checked for shorts and shorted sensors and didn't find any. I measured 5V at the sensor wires. The oil switch is working- goes from being grounded with the engine off to open once the motor is started and oil pressure opens it up. I don't know if the motor is in SLOW mode. I throttled up at the dock and it seemed to rev up but his tach isn't working (since well before this) so I can't swear I got it up over 2500 rpm.
I found a copy of the "7742218 Diagnostic Book" and went through as much of the troubleshooting on pages 252-255 that I understood. One of the later tests is to disconnect the J-1 connector at the ECM and turn the key; the horn should not sound. This one did. In that case, it said to check for another grounding source, possibly with the harness or Pin 4 in the 10 pin connector. I traced the wiring to the J connector and found no short in the sensor wires. I pulled the 10 pin connector and the wire to the alarm horn is not grounded.
I'm out of ideas. I can't check the ECM for codes and have no idea how to test the ECM itself. I'm not even clear on whether the alarm could mean something other than the overheat or oil pressure sensors grounding. The diagnostic book makes it sound like those sensors (or some unintentional short) are the only thing that could cause the beeping.
Any thoughts of what I'm missing or should try next?
Thanks in advance.
Mike
Sorry, I didn't think to write down the complete motor model and serial number but the boat is 2002 with 5.0GXi. I was hoping to get some suggestions of things to check before I go down there again- I'll get the complete numbers then.
He was at no wake speed and the audible alarm started. It's "beep beep", maybe a bit longer than it takes to say it out loud. Then quiet for a bit longer than the time of the beeps and then repeat... forever. All his gauges showed normal so he idled back to his slip. I went down the next day and it does it from a cold start and never stops.
At start, everything seems normal- the alarm gives two test beeps when the key is turned. Then nothing until the motor starts and immediately the beeping starts. I removed the wires to the exhaust risers and the oil pressure switch (spade connector, port, aft, over original oil filter location). I first disconnected one at a time and then all of them. I waited for over a minute. There's plenty of oil and the gauge shows pressure. Nothing felt unusually hot and the temp gauge shows normal and yet it continues to beep.
I checked for shorts and shorted sensors and didn't find any. I measured 5V at the sensor wires. The oil switch is working- goes from being grounded with the engine off to open once the motor is started and oil pressure opens it up. I don't know if the motor is in SLOW mode. I throttled up at the dock and it seemed to rev up but his tach isn't working (since well before this) so I can't swear I got it up over 2500 rpm.
I found a copy of the "7742218 Diagnostic Book" and went through as much of the troubleshooting on pages 252-255 that I understood. One of the later tests is to disconnect the J-1 connector at the ECM and turn the key; the horn should not sound. This one did. In that case, it said to check for another grounding source, possibly with the harness or Pin 4 in the 10 pin connector. I traced the wiring to the J connector and found no short in the sensor wires. I pulled the 10 pin connector and the wire to the alarm horn is not grounded.
I'm out of ideas. I can't check the ECM for codes and have no idea how to test the ECM itself. I'm not even clear on whether the alarm could mean something other than the overheat or oil pressure sensors grounding. The diagnostic book makes it sound like those sensors (or some unintentional short) are the only thing that could cause the beeping.
Any thoughts of what I'm missing or should try next?
Thanks in advance.
Mike