[DIYguy]

Oh! ya!... hold on, I do have a function generator!!!

http://www.toolstation.com/images/li...rand=811593264

[lazzer408]

Wow it'd be nice if I could read a wiring diagram today. lol I mis-marked the negitive terminal of the tach as L not - because I got lost in the connector numbering. (corrected pic attached)

The data line diagrams for your truck show nothing going to the cluster.

That tach is driven by a pulse.

[DIYguy]

Originally Posted by lazzer408

Wow it'd be nice if I could read a wiring diagram today. lol I mis-marked the negitive terminal of the tach as L not - because I got lost in the connector numbering. (corrected pic attached)

The data line diagrams for your truck show nothing going to the cluster.

That tach is driven by a pulse.

Ok, so I will feed 12v + to 13, - to 8 (located on a different plug) and pulse to 15... and see what happens.

If I recall, the back of the tach that plugs into the cluster backplane, has 4 pins engaging...not three. Will have to double check that.

[lazzer408]

Originally Posted by DIYguy

Ok, so I will feed 12v + to 13, - to 8 (located on a different plug) and pulse to 15... and see what happens.

If I recall, the back of the tach that plugs into the cluster backplane, has 4 pins engaging...not three. Will have to double check that.

It shows 4 connections to the tach in the diagram. I'm guessing pin8 (-) travels through it to another pin to provide neg to some of the other gauges/lamps. The "charge gauge" must be a voltmeter? You'll see that read the voltage you put to 13(c214) and 8(c216). Then your sig-gen ground on 8(c216) and pulse on pin 15(c214).
Next thing would be to drive your sensor's output right to pin 15 and see if it springs to life. With power/ground/signal all available at the tach it wouldn't be hard to run a shielded cable from there right to the sensor.

[DIYguy]

Originally Posted by lazzer408

It shows 4 connections to the tach in the diagram. I'm guessing pin8 (-) travels through it to another pin to provide neg to some of the other gauges/lamps. The "charge gauge" must be a voltmeter? You'll see that read the voltage you put to 13(c214) and 8(c216). Then your sig-gen ground on 8(c216) and pulse on pin 15(c214).
Next thing would be to drive your sensor's output right to pin 15 and see if it springs to life. With power/ground/signal all available at the tach it wouldn't be hard to run a shielded cable from there right to the sensor.

Sounds like a plan!
Thanks Lazzer!

[Jimdear2]

Originally Posted by DIYguy

Sounds like a plan!
Thanks Lazzer!

DIYguy,

Sounds like you two guys are this >< close to sucsess.

Lazzer seems to be right on top of everything. Ive been following along. I'm a MOTOR information / Alldata guy (I help write the stuff). He has been about a page ahead of me with his research.

Are you using the file as a pulse generator as someonr suggested (a neat and simple idea) or something else.

I can suggest a less elegant, quicky soulotion using a drill motor tied/strapped to a piece of wood. A two inch length of 1 x 1/8 flat stock with a hole drilled in the center. Put a bolt and nut through the center and clamp the resulting two pole reluctor into the chuck. A suitable plumbers strap bracket to hold a proximity sensor near the reluctor. Then wire as required and you will have a simple signal generator with a known rpm.

Here is wishing you sucsess.

[DIYguy]

Originally Posted by Jimdear2

DIYguy,

Sounds like you two guys are this >< close to sucsess.

Lazzer seems to be right on top of everything. Ive been following along. I'm a MOTOR information / Alldata guy (I help write the stuff). He has been about a page ahead of me with his research.

Are you using the file as a pulse generator as someonr suggested (a neat and simple idea) or something else.

I can suggest a less elegant, quicky soulotion using a drill motor tied/strapped to a piece of wood. A two inch length of 1 x 1/8 flat stock with a hole drilled in the center. Put a bolt and nut through the center and clamp the resulting two pole reluctor into the chuck. A suitable plumbers strap bracket to hold a proximity sensor near the reluctor. Then wire as required and you will have a simple signal generator with a known rpm.

Here is wishing you sucsess.

Thanks Jim! I appreciate the well wishes. I decided to take the instrument cluster out, move it to the motor department and since I now have my motor installed, I can use it directly to generate the signal. I figured that if it works this way...it has to work later.

cheers.

[DIYguy]

Originally Posted by lazzer408

It shows 4 connections to the tach in the diagram. I'm guessing pin8 (-) travels through it to another pin to provide neg to some of the other gauges/lamps. The "charge gauge" must be a voltmeter? You'll see that read the voltage you put to 13(c214) and 8(c216). Then your sig-gen ground on 8(c216) and pulse on pin 15(c214).
Next thing would be to drive your sensor's output right to pin 15 and see if it springs to life. With power/ground/signal all available at the tach it wouldn't be hard to run a shielded cable from there right to the sensor.

Verdict is.... SUCCESS!
Two pulses per revolution and tach reads correctly for motor rpm! I'm very pleased as I won't have to change anything related to my pulse generator. The frequency is fine too... I mis-judged that. 3000 pulses per second is way more than enough. I checked out the back of the cluster with my meter and figured which pin was for what. # 13 and 15 were correct however, the ground was actually in the second position on the other connector... not sure why. You were right about the volt meter too. When I put 12 volts to the panel, it came up almost half way. There was a common ground as you mentioned.

I actually shot a short video, or two rather. Not sure if I will have success uploading as last time I tried, the file size was too large.

I also took a few minutes to zero out my odometer. This thing is due to start over again! lol

[Jimdear2]

Originally Posted by DIYguy

Verdict is.... SUCCESS!
Two pulses per revolution and tach reads correctly for motor rpm! I'm very pleased as I won't have to change anything related to my pulse generator. The frequency is fine too... I mis-judged that. 3000 pulses per second is way more than enough. I checked out the back of the cluster with my meter and figured which pin was for what. # 13 and 15 were correct however, the ground was actually in the second position on the other connector... not sure why. You were right about the volt meter too. When I put 12 volts to the panel, it came up almost half way. There was a common ground as you mentioned.

Wonderfreekingful.

So it was 2 pulses afrer all.

If you find out why the thing didn't work when you hooked the pulse generator signal lead to the tan and yellow lead, let me know. That thould have worked. I assume you did have the instrument cluster powered and pulse generator powered from the same source when you tested and you did have the tan/yellow disconnected from the PCM. Not that it matters, IT works . . . I'm just curious.

Originally Posted by DIYguy

I also took a few minutes to zero out my odometer. This thing is due to start over again! lol

A hint here. Agencies which shall remain nameless get upset when you fool with a vehicles odometer. Like big fines or vacations in their facilities.

Check with your States vehicle registration agency and see if they have a odometer replacement form and or sticker. If you go for inspection with a zeroed odometer and no sticker/form it might get sticky.

It may be a nothing problem in your state, but be SURE it is.

[DIYguy]

Originally Posted by Jimdear2

Wonderfreekingful.

So it was 2 pulses afrer all. .

yup, you were right about that... and I'm glad because I built my pulse generator based on your information.... and I don't have to change a thing.

Originally Posted by Jimdear2

If you find out why the thing didn't work when you hooked the pulse generator signal lead to the tan and yellow lead, let me know. That thould have worked. I assume you did have the instrument cluster powered and pulse generator powered from the same source when you tested and you did have the tan/yellow disconnected from the PCM. Not that it matters, IT works . . . I'm just curious..

I'll let you know... not sure why. I did exactly as you describe above.

Originally Posted by Jimdear2

A hint here. Agencies which shall remain nameless get upset when you fool with a vehicles odometer. Like big fines or vacations in their facilities.

Check with your States vehicle registration agency and see if they have a odometer replacement form and or sticker. If you go for inspection with a zeroed odometer and no sticker/form it might get sticky.

It may be a nothing problem in your state, but be SURE it is.

Ya, they don't like it here in Canada either. I decided to go for it even though I was aware of that. I will just tell them about it and do the form or whatever they want. It aint gonna stop me.