[econolinedude]

Hi everyone, I have been busy to swap 2000 mod F-250 7.3 PSD instrument cluster to my -98 E-350 7.3 PSD.
It was quite easy to get that cluster in place, I had to gut off one mounting ear. Switched around some wires on those 3 connectors, found that CTO labeled W/PK wire above brake booster, and get it to place nr12 on that longest white connector in the middle of cluster. So far so good.
Started engine up, and find out that ABS light was on and tach showed about 1900 rpm on idle…(680 rpm is right.. I think??) And driving 55mph it shows about 4600 rpm. It has 3.55 gears. Everything else was just right.
So, tach signal on -98 PSD is reflected CMP signal, and it is 130 – 720 Hz range, on 6.5 v. And based on Service Information 1.53 © 2001 Ford Motor Company, it’s the same on 2000 F-250 PSD.

But I’ve read some place that tach signal is lower impulse on -99 up F series than -98 E series??
I tried lower that tach impulse with 10 K ohm and 100 K ohm, but it doesn’t help out.

I’ve been seen http://www.esiacquire.com/TachChangerPage.htm for help in this issue… But living here in Norway, long gone from any shop with that kind of things for sale L… I like to hear if there is somebody who has experience with this equipment before I order it from USA…

Thanks for any response and sorry for my English is not so good… many years ago when I learn it in school...

 

[joeblack5]

tach swap

Hi Ecodude,

Is your odo meter electronic or mechanical. Does the the 2000 have exactly the same PSD?
I want to try the same on my 1997 psd, mechanical odo,

may be your tach is sensitive for up going signal and down going signal resulting in factor 2 different. factor three is strange unless the 2000 has the 6.0 different psd motor??

Do you have the connector identification and pin identification in an electronic format that you could post / forward? Where did you get the info to of the cto wire,
Sorry I could not help you but please let us know .

Very nice country, drove once to the north cape in a NIVA diesel.

later J

 

[econolinedude]

Hi joeblack5…

Yes my odometer is mechanical, as it is on 1999 - 2001 Excursion, Super duty series F-250, F-350, F-450, F-550. My donor vehicle was 2000 F-250 7.3 PSD.

There are 3 connectors on backside of cluster, one white 16 pin, one white 12 pin and one black 12 pin connector.

A few wires need to be switched around in the harness connectors. That’s why you must get all those 3 connectors with little bit wires on them from your donor vehicle. Then it’s easy to compare it to your -97 model and get around and change the pin locations.

On 1998 7.3 PSD E-350 signal wire to tach is WH/PK (white with pink trace). It comes from PCM (Power Train Control module), and ends the outside of wire harness just left side of the brake booster, when you stand front of your van. It’s labelled CTO. But, the label can be missing… look at the colour of the wire, and it is not going anywhere, it just ends there.
You can only use multimeter to measure it. Key off: 0v. Key on: 12v, on idle it should have 6.5v.
I’m not sure if -97 has different layout on this, probably not. You find some pictures on my profile pictures, hope it will help you.

 

[joeblack5]

tach for 97 E350 psd

Econolinedude,

Thank you for your help and direction.
I have ordered a cluster as you advised.
I think that the tach is dedicated and a such I hope not to difficult to change the timing. Older style tacho's use a monoflop or one shot to transform the pulse train from the engine to a dc voltage , frequency ( RPM) linear with output voltage. If this is the case in this cluster then it should not be difficult to modify.
The gauge parts of the original cluster are complicated because they are micro processor controlled and internally use a serial bus for the air gap gauges.
I am curious why Ford went through that complicated process instead of reading the sensors out directly?
Thank you again for directing me in the right direction.

later J

 

[joeblack5]

e350 tach 1997

received a correct diesel cluster .
I am modifying the wiring on the cluster so that the old cluster can be put back in.
Noticed a small adjustment potentiometer left of the middle connector ( tach side) Wonder if this adjusts the tach?

It is nice, mu VAN is converted to 4x4 so now I can connect the 4x4 and low range light as well.

I will have this one hooked up next week ans sse if it works.

Later J

 

[joeblack5]

1997 diesel e350 4x4 tach

Ok, here are my results,

Rewired the back side of the new 99 F 4x4 series cluster. I wanted to stay pin compatible with the old cluster in case of problems.

When done it physically did not fit. closer comparison shows that the left top tab is in a slightly different location.

I took the acrylic part and the bezel of the the van's original cluster and mounted it on the F series circuit board and gauge part, It shows that the other three holes are slightly off as well. I cut the left top tab off.
The screws fit now with some wiggling.

The wiring pages I found on Econolinedude's show that there are two tach lines. One tach line is connected the pcb to two pins of the connector.
I disconnected that trace with a dremel and soldered two wires to the PCB for testing purposes.

I also applied battery power to the connector and noticed that the fuel gauge went to full.
Connecting resistors to the gauge inputs and ground made the gauges change.
Oil pressure gauge always goes to the same location below a certain resistance and above that resistance shows zero.
I forgot to test the temp gauge and only noticed that with zero resistance it shows in the middle.
I also soldered wires to the 4x4 and low range indicator lights , nice for the quigley.


After this I mounted the cluster in van, everything worked.
Then the tach only one of the wires shows a reasonable RPM ( 700 idle) and that with a 10K resistor in series with CTO, the other wire has to be loose.
At 55 mph on the speedo the tach shows 1550 rpm , my ratio is I believe 3.55. Did not do the math yet.

later J

 

[Ball]

Anybody know if the CTO is a 12v square wave tach signal, or does that signal not exist on PowerStrokes.

I have a '95 7.3 and want to use a 3d party tach if at all possible.

 

[joeblack5]

Finally, after 4 years , calibrating the factory..
With some powerstrokes or clusters the tach reads twice the actual RPM.
The potentiometer on the back side of the cluster does not bring the tach in the range
Opened up the cluster and found an air core tach chip CS8190. You can google it for the data sheet and schematic. With the schematic I was able to find what component to change to make it work correctly.
I connected an 220 K ohm resistor in the circuit board parallel to the R19 smd resistor. This is part of the Rt resistor in the cs8190 schematic. The r19 is 182 kohm. the minimum value for rt is 100k ohm. The 220 k in parallel brings it close to the minimum 100K. Good enough now you can adjust the pot meter o that the tach reads correct.
I have posted a picture on skoolie.net Look for Elf bus E350 Corbeil II photo album.

Later J