Tach Gauge--Time To Replace?

[zenoahphobic]

[QUOTE=TownsendsFJR1300;120033]Are you disconnecting the entire tach and just applying voltage and ground to the tach for your test?


Jason, I was trying to PM you but you have it turned off.


Baha, I also have / use the OMC Triple guard grease (also good for mid section bushing).

Is there ANY issues with it carrying current between adjacent contacts?? (IE, is it conductive?)

I've used dielectric grease for years and have not had to do any "do-overs" from failure. Doesn't take much either..[/QUOTE

I think the problem with using "normal" grease is that it does not conduct electricity but moreso is that it can "harden" producing electrical insulation at the contacts. The idea of using any grease dielectric or not is the same reason for using any lubrication is for the parts to slide onto each other giving optimum surface contact. This needs to be weighed against the insulation that it also gives. Most electrophiles(?) will always argue that a clean and "dry" connection always.

[Jason2tpa]

[QUOTE=zenoahphobic;120117]

Are you disconnecting the entire tach and just applying voltage and ground to the tach for your test.

I've tested tach both ways while connected directly to power & ground...with the 2 tach harnesses connected and disconnected, including disconnecting green and blue wires from tach.

No one has responded to my question as to what the tach should show when hooked directly to power. Be that as it may, i assume the tach should show something. And when i hook to power im not getting anything.

[TownsendsFJR1300]

IDK how you would further test it. Someone else (I hate electric's) will have to chime in...

[boscoe99]

[QUOTE=Jason2tpa;120293]

I've tested tach both ways while connected directly to power & ground...with the 2 tach harnesses connected and disconnected, including disconnecting green and blue wires from tach.

No one has responded to my question as to what the tach should show when hooked directly to power. Be that as it may, i assume the tach should show something. And when i hook to power im not getting anything.

With 12 volts connected to the blue lead next to the black lead, and with the black lead next to the blue lead grounded, I would expect the back light to illuminate.

With 12 volts connected to the yellow lead next to the other black lead, and with the black lead next to the yellow lead grounded, I would expect the tachometer to come to life. By that I mean the 0 for the RPM's should appear and the liquid crystals for the trim bars should illuminate. I seem to recall that all bars will be shown with the top one flashing. Now if there are two black wires with the yellow wire then ground both of them.

Find the pin for the orange wire that comes from the tachometer. There should be five volts on it. With power and ground to the yellow wire and the ground wire(s). For the rest of the wires, ground them one at a time.

The pink wire should cause the trim bars to decrement. The gray wire should cause the over temperature light to illuminate. One of the wires should cause the red light to illuminate. One of the wires should cause the green light to illuminate.

'sperment man.

http://www.boats.net/parts/search/Ya...201/parts.html

[Jason2tpa]

Bossman....from back of tach ive got the 2 separate harnesses. Then ive got 4 independent wires...yellow, black, blue, and green. One of each. Correct me if im wrong, blue is trim/backlight, green is tach signal, yellow is power, black is ground. If im correct, when i hook jumper wires to yellow and black to battery power and ground im not getting anything on screen. Same result if i leave blue wire connected to blue from harness and green connected from harness. Only diff is if I disconnect blue the backlight doesnt come on...which it shouldnt if disconnected.

[QUOTE=boscoe99;120305]

With 12 volts connected to the blue lead next to the black lead, and with the black lead next to the blue lead grounded, I would expect the back light to illuminate.

With 12 volts connected to the yellow lead next to the other black lead, and with the black lead next to the yellow lead grounded, I would expect the tachometer to come to life. By that I mean the 0 for the RPM's should appear and the liquid crystals for the trim bars should illuminate. I seem to recall that all bars will be shown with the top one flashing. Now if there are two black wires with the yellow wire then ground both of them.

Find the pin for the orange wire that comes from the tachometer. There should be five volts on it. With power and ground to the yellow wire and the ground wire(s). For the rest of the wires, ground them one at a time.

The pink wire should cause the trim bars to decrement. The gray wire should cause the over temperature light to illuminate. One of the wires should cause the red light to illuminate. One of the wires should cause the green light to illuminate.

'sperment man.

1989 115ETLF Yamaha Outboard OPTIONAL PARTS GAUGES & COMPONENT PARTS 1 Diagram and Parts

[Jason2tpa]

Also, my model yr is '98 S115TLRW. Unless the tach i have is the same of '89

1989 115ETLF Yamaha Outboard OPTIONAL PARTS GAUGES & COMPONENT PARTS 1 Diagram and Parts

[99yam40]

[QUOTE=Jason2tpa;120589]Bossman....from back of tach ive got the 2 separate harnesses. Then ive got 4 independent wires...yellow, black, blue, and green. One of each. Correct me if im wrong, blue is trim/backlight, green is tach signal, yellow is power, black is ground. If im correct, when i hook jumper wires to yellow and black to battery power and ground im not getting anything on screen. Same result if i leave blue wire connected to blue from harness and green connected from harness. Only diff is if I disconnect blue the backlight doesnt come on...which it shouldnt if disconnected.


If you get nothing when you power up the yellow+ and black-, I would think the tach does not work

[Jason2tpa]

Hey yam. Sorry shud have provided more detail. Tach turns on but doesn't show what boscoe said. What i barely see is a indistinguishable number, few trim bars, few arrows. But you can hardly even make that out.

[TownsendsFJR1300]

Sounds like its toast....

[99yam40]

still it does not work if it does not show anything that is readable

[Jason2tpa]

still it does not work if it does not show anything that is readable

Agreed. Before investing in a new one i wanna make sure the issue isn't electrical. Dunno if the dimming could be caused by short.

[TownsendsFJR1300]

Agreed. Before investing in a new one i wanna make sure the issue isn't electrical. Dunno if the dimming could be caused by short.

A short inside the unit maybe...

You already know the unit itself is NOT working properly. You've plugged it
in outside the system with crappy results.

I'd look on Flea Bay for a used unit, Pay Pal guarentees the purchase if you get another bad one...

[Jason2tpa]

Gotcha. Do you know if my model/yr can use the tach with MODE & SET buttons? Or must I get the same one.