Trim / Tilt sensor test readings

[fishintech]

I have a 1984 90hp and I'm having trouble finding test readings for the trim/tilt sensor and gauge. The gauge gets battery voltage at key on through the yellow wire and has four wires (pink, orange, grey, and black) that go directly back to the sensor. Can anyone tell me what voltage readings should be coming from the gauge, and what resistance readings I should be getting from the sensor? Any help would be greatly appreciated.

Thanks, Steve

[Ken]

fishintech,
That grey wire in the harness should break out and go to the alarm buzzer under the console.
The pink, orange, and black go to the trim sensor.
According to my shop manual for a 2000 C115, the resistance measurements are as follows: (disconnect the plug on the wire harness that should be a few feet away from the trim sensor and probe the pins there) - slowly move the trim sensor arm thru its range and you should read the following:

pink to black: 582 to 873 ohms
orange to black: 800 to 1200 ohms

Hope this helps [img]smile.gif[/img] ,
Ken K

[fishintech]

Ken,
Thanks for the info but I don't know if test readings for a 2000 C115 are going to be the same for my engine. I'm pretty sure the sensor is bad because the readings I get are steady throughout it's entire range of travel. Current readings with the wiring harness disconnected are; grey to black: 1 kohm, orange to black: 2.1 kohm, and pink to black: 6.5 kohm.

Voltage readings coming from the gauge with the sensor diconnected are as follows: Grey to gnd. 4.0 V, Orange to gnd. 11.5 V, pink to gnd. 0 V.

As far as the grey wire is cocerned, it goes directly from the sensor to the gauge and doesn't branch off anywhere. What warning buzzer is it for?

The thing that's got me perplexed is that, I am just wrapping up doing a complete re-wire on this boat, except I didn't touch the factory engine or gauge wiring, and the gauge was working fine before.

I've got a Seloc idiot manual with a wiring diagram, but it doesn't have any test procedures or readings for the trim system. I would post the diagram but I don't see any way to attach it.

If you have any more info I'm all ears.

Thanks, Steve

[fishintech]

Ken,
Thanks for the info but I don't know if test readings for a 2000 C115 are going to be the same for my engine. I'm pretty sure the sensor is bad because the readings I get are steady throughout it's entire range of travel. Current readings with the wiring harness disconnected are; grey to black: 1 kohm, orange to black: 2.1 kohm, and pink to black: 6.5 kohm.

Voltage readings coming from the gauge with the sensor diconnected are as follows: Grey to gnd. 4.0 V, Orange to gnd. 11.5 V, pink to gnd. 0 V.

As far as the grey wire is cocerned, it goes directly from the sensor to the gauge and doesn't branch off anywhere. What warning buzzer is it for?

The thing that's got me perplexed is that, I am just wrapping up doing a complete re-wire on this boat, except I didn't touch the factory engine or gauge wiring, and the gauge was working fine before.

I've got a Seloc idiot manual with a wiring diagram, but it doesn't have any test procedures or readings for the trim system. I would post the diagram but I don't see any way to attach it.

If you have any more info I'm all ears.

Thanks, Steve

[Ken]

Steve,
Yeah, I think you are correct about the two models being different on the wiring.
But, still, with the trim/tilt harness disconnected, you should be measuring some change in resistance between the wires as you move the t/t lever thru its range.
That grey wire on my boat is bundled with the three wires that connect the t/t sensor and the gauge, and it comes from the thermo-switches that are mounted in the heads to indicate an overheat condition when they get to approx 180 degrees f.
I believe the grey wire goes to the alarm buzzer under the console on my boat.
Hope this helps, and let us know how you come out [img]smile.gif[/img] ,
Ken K