BF225A Problems with Tach + Tilt indications after O2 sensor replacement?

OK I have a problem with indications for both the trimmeter and the tachometer. They were working fine before the boat went in to the shop for warranty work on O2 sensor and now they don't work! Motor still runs and full movement trim but no indications?

Any clues as to why? Maybe a connector left un-plugged? Hopefully something simple!

Not sure what warranty work was done....but why don't you call the dealer? They would know more about what they had to take apart and may be able to lead you right to the problem.

It may be totally unrelated. It will be helpful for them and us....

-Do the other gauges work?
-Do the trim and tach even move when you turn the key switch to on?
-Is the tach needle at zero or is it at a higher number? Tach should go to zero when you turn on the key switch?
-Do you get all the warning lights come on for two seconds (with a beep) when you turn the key switch to on?

Mike

O2 sensor was replaced, I did call after getting the boat back in the water but no clues.
Other guages appear to work, have backlights on all guages.
I will have to check again if there is deflection on tach when I key on but presently it is at rest at 2000rpm, trimmeter stuck at bottom.
All warning lights and beep do register when keyed on.
Motor starts and runs nicely.
Trim has full motion, up /down.
I see from the dia. that the trimmeter sends one line to the "ECM" and so does the Tach, they are the only lines not common to each other.

hondadude said:

Not sure what warranty work was done....but why don't you call the dealer? They would know more about what they had to take apart and may be able to lead you right to the problem.

It may be totally unrelated. It will be helpful for them and us....

-Do the other gauges work?
-Do the trim and tach even move when you turn the key switch to on?
-Is the tach needle at zero or is it at a higher number? Tach should go to zero when you turn on the key switch?
-Do you get all the warning lights come on for two seconds (with a beep) when you turn the key switch to on?

Mike

Click to expand...

Ok, so I wrung out all wires in bundle back from wheelhouse to motor (where they meet in a green plug with 14 wires) All show continuity.
I went to the Trim sensor and shorted the Y/Bu first to the Bl end and then to the Lg/Bl end (sensor is a simple rheostat) and no change to indicator.

I spoke with the Honda shop again and am now going to check an in-line fuse on the common Bl/Y wire from back of guages, ( though if I already checked continuity back to Green plug I'm pretty sure it is going to be intact).

Cpn Bird's eye said:

O2 sensor was replaced, I did call after getting the boat back in the water but no clues.
Other guages appear to work, have backlights on all guages.
I will have to check again if there is deflection on tach when I key on but presently it is at rest at 2000rpm, trimmeter stuck at bottom.
All warning lights and beep do register when keyed on.
Motor starts and runs nicely.
Trim has full motion, up /down.
I see from the dia. that the trimmeter sends one line to the "ECM" and so does the Tach, they are the only lines not common to each other.

Click to expand...

Cpn Bird's eye said:

Ok, so I wrung out all wires in bundle back from wheelhouse to motor (where they meet in a green plug with 14 wires) All show continuity.
I went to the Trim sensor and shorted the Y/Bu first to the Bl end and then to the Lg/Bl end (sensor is a simple rheostat) and no change to indicator.
I spoke with the Honda shop again and am now going to check an in-line fuse on the common Bl/Y wire from back of guages, ( though if I already checked continuity back to Green plug I'm pretty sure it is going to be intact).

Click to expand...

In-line fuse intact on BL/Y wire.

I put a meter across the signal, Y/Bu, to ground, Bl, and recorded 2.97 VDC and then lifted motor full up and recorded 3.3VDC, is this normal output for the sensor?

What voltage should I be able to measure from the signal, Gr, on the Tach when running the motor?

Voltage to the trim meter is normal. Not sure what should be on the Gr lead to tach.

You never did say if you are getting power to those two gauges. I think that is your problem.

Should be 12v from the black/yellow to the black leads on both meters when the key switch is turned on. If not, check the in line fuse in the gauge wiring harness (if it is a Honda Harness). Otherwise, just make sure the black lead is truly grounded and then follow the yellow/black lead until you find 12v.

Mike

hondadude said:

Voltage to the trim meter is normal. Not sure what should be on the Gr lead to tach.

You never did say if you are getting power to those two gauges. I think that is your problem.

Should be 12v from the black/yellow to the black leads on both meters when the key switch is turned on. If not, check the in line fuse in the gauge wiring harness (if it is a Honda Harness). Otherwise, just make sure the black lead is truly grounded and then follow the yellow/black lead until you find 12v.

Mike

Click to expand...

Yes, I do get 12VDC on the Bl/Y wires. The Tach needle is stuck at jusy below 2k rpm, however when I measure for voltage on the signal wire, Gr, I read appx 40mv at idle and 1.5BVDC when I increase rpm to about 2500rpm (est)

If you get 12v and ground at the gauge when you turn the key switch to on and the needle stays stuck at 2k rpm, then the tach is bad or the needle is physically stuck. In any case, it is bad.

I would also check for 12v and ground at the trim gauge. Don't pick up the ground somewhere else, get it right at the gauge.

Mike

Around the same exact time I had my ECU changed due to 02 sensor warrenty letter I recieved. So too my trim/tilt gauge started acting up.

Worked fine before I took boat in for the service.


I checked for loose wires, thats all. But my gauge has the trim level pointer point straight up most of the time. Then, sometimes it just starts working again, during the day. Coincodence?

I didn't find any loose wires thought.

Lock your motor in the full up position. Find the spring-loaded tilt-trim sensor arm on the back of the motor - it's on the left as you are looking forward. First, make sure it is not sticking. If it is, pull it off and lubricate. It's not unusual to get sand, sludge, or mud lodged in there. Have someone turn the key to the ON position and watch the gauge while you manually work the tilt/trim sensor arm and see if the gauge corresponds with your movements. If so, it is just sticking. If not, follow the lead from the sensor into the lower cowling to find the plug, pull the plug apart and clean the contacts.

If that does not fix the problem, then go to your gauge and check the connections, especially the ground wire. Test the resistence between the gauge ground and system ground. It should be very near zero.

I have the same problem with a 200hp honda. Was there ever a definitive answer?

seabobpow - start another thread on this forum and state the precise issue.