Page 1 of 1

Gauge readings

Posted: Sun Apr 03, 2022 4:51 pm
by Corndog
A gauge is of no use unless you know what you should ge looking for. Temperature on the sync 3 screen tell me it's 17° outside. Temperature gauge on the dash sits around the bottom of the thermometer bulb picture. Auto transmission temp, who knows. This is the norm. Added some gauges on my phone from obdlink, engine coolant temp and transmission fluid temp. They show around 80° for water and 90/95 for transmission from a trip I've done. Its a 3.2 Ranger with canopy, rear drawers and some tools in them, so a little extra weight but not much.
Question is what are the readings others are getting and do these seem to be about right?

Re: Gauge readings

Posted: Sun Apr 03, 2022 7:29 pm
by RossPat
Only being an ambient temp of 17 those temps are about right
Expect the water to read around 90 and trans 95/100 when the ambient temperature is around 30
Of course there will be variations, humidity & wind direction/speed for a start

Re: Gauge readings

Posted: Sun Apr 03, 2022 7:42 pm
by Corndog
Thanks.

Re: Gauge readings

Posted: Thu Apr 21, 2022 10:41 pm
by Corndog
I'm having a play with tyre pressure gauges. Have created the four checked the pressures at the servo and then with my hand pressure gauge. Dont know all about the equation but they were reading high so adjusted the last figure from 0.145 to 0.095 to get a closer reading for each gauge. Is this the correct way to adjust it?
Also had to change the PID numbers around to match the tyre positions.

Re: Gauge readings

Posted: Sat Apr 23, 2022 8:56 pm
by saeb
** Note calculated figures are Barometric Compensated and not many instruments will take that into account.

** If you have to change the PIDs around then your tyres have been rotated and not retrained to the new position. Upon doing this your PIDs would be correct.

Anyway....

Interesting enough you made me look at my guessed equations from 5 years ago. They were slightly wrong but not in the way you want them to be as my old ones where slightly low.

Up to you what you do with this but these calcs are from genuine documents so are 100% the correct equations.

The equations in the calc are and the 0.145 is to convert from kPa to PSI so changing that figure is not ideal. But there is a way if you are sure your instruments are 100% correct.

Maths for all 4 PIDS should be changed to;

((A*256)+B)*1723690/5000000*0.145

In your case, if you wanted to minus 2 PSI then

((A*256)+B)*1723690/5000000*0.145-2

Change this figure to whatever you like.


The BCM outputs the figures in kPA so that is why we need to *0.145 to convert to PSI.

Checking with Ford IDS logging my own figures then comparing CANBUS messages, my below figures are in the below image.