Jump to content
LegacyGT.com

Trip meter hacking thread

CombatCQB

By CombatCQB
in Interior/Audio

Recommended Posts

  • 1 month later...
  • Replies 98
  • Created
  • Last Reply
  • 1 month later...
tarambuka3500 Rookie

tarambuka3500

Posted
Posted

yes and no :)

the display itself is not *universal* and can accept & show only certain values.

e.g. you cant' make it show each and every value that one think should be possible, using XX.Y format.

 

so code is a mix between mathematical conversion and additional logic to make the converted values *compatible* with the display.

 

but at the end it all works properly.

Link to comment
Share on other sites
  • 4 weeks later...
brou4164 Enthusiast

brou4164

Posted
Posted

Complete novice here; please go easy:

 

Are y'all talking about modifying the programming to calculate the trip meter & MPG calculator to be more accurate? I.E. account for injector upgrades, etc? I've been hunting for a while to see what's the deal, (if this needs to be done or if the computer can adjust for said changes) because I upgraded my injectors to 1150cc & would really like accurate readings.

 

Any and all guidance would be greatly appreciated!

Link to comment
Share on other sites
tarambuka3500 Rookie

tarambuka3500

Posted
Posted

Are y'all talking about modifying the programming to calculate the trip meter & MPG calculator to be more accurate? I.E. account for injector upgrades, etc?

 

No - we're talking about making it show the values in Liters/kilometers/celsiues (e.g. metric units) instead of MPG/miles/Fahrenheit (imperial).

 

However what you need is also doable, if you know the mathematics

e.g. if you can calculate the difference by hand, the car can be *fixed* to show the updated values.

Link to comment
Share on other sites
brou4164 Enthusiast

brou4164

Posted
Posted

Thank you for clearing all that up! I do actually know the formula in order to fix this issue... I just have no clue how to actually do it.

 

The instant mpg is based on the injector size (520cc) and so I would just need to replace that info with my new injector size (1150cc). Do you think y'all can help?

Link to comment
Share on other sites
  • 2 weeks later...
  • 4 weeks later...
tarambuka3500 Rookie

tarambuka3500

Posted
Posted

here's how it all works/looks :)

first display is the metric one+convertor IC, second is the original (imperial units)

 

[ame=http://www.youtube.com/watch?v=xEu0fNIso_M]‪US Subaru Outback trip computer replaced with metric version [all working!]‬‏ - YouTube[/ame]

 

finally I'll close my dash :)

 

and KUDOS to CombatCQB for all the research he did!!!

Link to comment
Share on other sites
  • 1 month later...
Zephrant Collaborator

Zephrant

Posted
Posted

Bump- Still looking to feed this in to the Car PC (Centrafuse desired, but I'd take anything). I don't want to relocate the display, but I'm tired of not having the outside temp and MPG.

 

Anyone know of those two things are available though the OBD-II port?

Link to comment
Share on other sites
  • 3 months later...
  • 1 year later...
dahoseman Rising Star

dahoseman

Posted
Posted

I ran across this thread and thought I would resurrect it. I have a modified 05 Outback XT with an onboard trip calculator that no longer reads fuel-calculated information correctly.

 

I would be very interested in finding out how to implement changes to make the Instant MPG, AVG MPG, and range calculator more accurate. Over many trips and various manual calculation comparisons, I've found that changing stock injectors to 740CC has left the trip calculator reading at 1.48(actual) on all of accounts.

 

Avg MPG will read ~34mpg when actual (miles/gallons) turns out to be 23mpg

Range reads 510 miles to empty when actual turns out to be ~345

 

I have no programming experience, but I would be highly interested in learning how to make these changes

Link to comment
Share on other sites
tarambuka3500 Rookie

tarambuka3500

Posted
Posted

I would be very interested in finding out how to implement changes to make the Instant MPG, AVG MPG, and range calculator more accurate. Over many trips and various manual calculation comparisons, I've found that changing stock injectors to 740CC has left the trip calculator reading at 1.48(actual) on all of accounts.

 

Avg MPG will read ~34mpg when actual (miles/gallons) turns out to be 23mpg

Range reads 510 miles to empty when actual turns out to be ~345

 

I have no programming experience, but I would be highly interested in learning how to make these changes

 

It can be done easily by someone with embedded-programming experience.

Most of the info you need is in the thread. A small IC must intercepts the ECU feed, multiply the values by 1.48 and then feed to the display. That is all that's needed.

 

Same as what I have in my car, just different formula.

Link to comment
Share on other sites
  • 1 year later...
uncle humjaba Enthusiast

uncle humjaba

Posted
Posted

I'm working on replacing the clock module with a couple of screens... one fed by information from the ECU (ssm) and the other from the factory trip computer (mpg, etc). I was wondering if anyone had figure out how to make the airbag light go away? Is it just a matter of jumping pins 3 and 4 to ground through a resistor? http://legacygt.com/forums/showpost.php?p=1315335&postcount=692

 

 

Also, I have everything working when I talk to SSM but I can't get useful information from the UART line. It just seems to read gibberish. See here:

248	112	80	3	240	13	87	112	80
3	248	184	80	3	248	112	80	3
240	13	87	184	160	248	112	80	3
240	13	87	184	160	248	184	80	3
240	13	87	112	80	3	248	184	160
248	112	80	3	240	13	87	184	160
248	112	80	3	240	13	87	184	160
248	184	80	3	240	13	87	112	80
3	248	184	160	248	112	80	3	240
13	87	184	160	248	112	80	3	240
13	87	184	160	248	184	80	3	240
13	87	112	80	3	248	184	160	248
112	80	3	240	13	87	184	160	248
112	80	3	240	13	87	184	160	248
184	80	3	248	112	80	3	240	13
87	184	160	248	112	80	3	240	13
87	184	160	248	184	80	3	240	13
87	112	80	3	248	184	160	248	112
80	3	240	13	87	184	160	248	112
80	3	240	13	87	184	160	248	184
80	3	248	112	80	3	248	184	160
248	112	80	3	240	13	87	184	160
248	112	80	3	240	13	87	112	80
3	248	184	80	3	240	13	87	112
80	3	240	13	87	184	160	248	112
80	3	240	13	87	184	160	248	112
80	3	240	13	87	184	160	248	184
160	248	112	80	3	240	13	87	184
160	248	112	80	3	240	13	87	184
160	248	184	80	3	240	13	87	112
80	3	248	184	160	248	112	80	3
240	13	87	184	160	248	112	80	3
240	13	87	184	160	248	184	80	3
240	13	87	112	80	3	248	184	160
248	112	80	3	240	13	87	184	160
248	112	80	3	240	13	87	184	160
248	184	80	3	240	13	87	112	80
3	248	184	160	248	112	80	3	240
13	87	184	160	248	184	80	3	240
13	87	184	160	248	184	80	3	248
112	80	3	240	13	87	184	160	248
112	80	3	240	13	87	184	160	248
184	80	3	240	13	87	112	80	3
248	184	160	248	112	80	3	240	13
87	184	160	248	112	80	3	240	13
87	184	160	248	184	80	3	240	13
87	112	80	3	240	13	87	184	160
248	112	80	3	240	13	87	184	160

 

It's like it pretty routinely misses some bytes. Here's my code:

void setup() {
 // initialize serial:
 Serial.begin(9600);
 Serial1.begin(2400);
}

int count = 0;

void loop() {
if (Serial1.available()) {
	if (count == 9) {
		Serial.println(Serial1.read());
		count = 0;
	}
	else {
		Serial.print(Serial1.read());
		Serial.print("\t");
	}
	count += 1;
}
}

Link to comment
Share on other sites
  • 2 weeks later...
uncle humjaba Enthusiast

uncle humjaba

Posted
Posted

So I redid my wiring a bit and now I get this:

7	32	41	D0	41	5	6E	B8	20
7	32	41	68	81	5	6E	70	10
7	32	41	D0	41	5	6E	B8	20
7	32	41	68	81	5	6E	70	10
7	32	41	D0	41	5	6E	B8	20
7	32	41	68	81	5	6E	B8	10
7	32	41	68	41	5	6E	70	10
7	32	41	D0	41	5	6E	B8	20
7	32	41	68	81	5	6E	70	10
7	32	41	D0	41	5	6E	B8	20
7	32	41	68	81	5	6E	B8	10
7	32	41	D0	41	5	6E	70	10
7	32	41	68	81	5	6E	B8	20
7	32	41	68	41	5	6E	70	10
7	32	41	D0	41	5	6E	B8	20
7	32	41	68	81	5	6E	70	10
7	32	41	D0	41	5	6E	B8	20
7	32	41	68	81	5	6E	B8	10
7	32	41	68	41	5	6E	70	10
7	32	41	68	81	5	6E	B8	20
7	32	41	68	41	5	6E	70	10
7	32	41	D0	41	5	6E	B8	20
7	32	41	68	81	5	6E	70	10
7	32	41	D0	41	5	6E	70	10
7	32	41	68	81	5	6E	B8	10
7	32	41	D0	41	5	6E	70	10
7	32	41	D0	41	5	6E	B8	20
7	32	41	68	41	5	6E	70	10

 

The car isn't running, sitting with the key in the "on" position. Any ideas on what is what? How do I know? I have it start a new line every 9th byte but how do I know where the stop is?

Thanks

 

Code is:

void setup() {
 // initialize serial:
 Serial.begin(9600);
 Serial3.begin(2400);
}

int count = 0;

void loop() {
if (Serial3.available()) {
	if (count == 9) {
		Serial.println(Serial3.read(), HEX);
		count = 0;
	}
	else {
		Serial.print(Serial3.read(), HEX);
		Serial.print("\t");
	}
	count += 1;
}
}

Link to comment
Share on other sites
AkumaMax Experienced

AkumaMax

Posted
Posted
I'm working on replacing the clock module with a couple of screens... one fed by information from the ECU (ssm) and the other from the factory trip computer (mpg, etc). I was wondering if anyone had figure out how to make the airbag light go away? Is it just a matter of jumping pins 3 and 4 to ground through a resistor? http://legacygt.com/forums/showpost.php?p=1315335&postcount=692

 

 

Also, I have everything working when I talk to SSM but I can't get useful information from the UART line. It just seems to read gibberish. See here:

248	112	80	3	240	13	87	112	80
3	248	184	80	3	248	112	80	3
240	13	87	184	160	248	112	80	3
240	13	87	184	160	248	184	80	3
240	13	87	112	80	3	248	184	160
248	112	80	3	240	13	87	184	160
248	112	80	3	240	13	87	184	160
248	184	80	3	240	13	87	112	80
3	248	184	160	248	112	80	3	240
13	87	184	160	248	112	80	3	240
13	87	184	160	248	184	80	3	240
13	87	112	80	3	248	184	160	248
112	80	3	240	13	87	184	160	248
112	80	3	240	13	87	184	160	248
184	80	3	248	112	80	3	240	13
87	184	160	248	112	80	3	240	13
87	184	160	248	184	80	3	240	13
87	112	80	3	248	184	160	248	112
80	3	240	13	87	184	160	248	112
80	3	240	13	87	184	160	248	184
80	3	248	112	80	3	248	184	160
248	112	80	3	240	13	87	184	160
248	112	80	3	240	13	87	112	80
3	248	184	80	3	240	13	87	112
80	3	240	13	87	184	160	248	112
80	3	240	13	87	184	160	248	112
80	3	240	13	87	184	160	248	184
160	248	112	80	3	240	13	87	184
160	248	112	80	3	240	13	87	184
160	248	184	80	3	240	13	87	112
80	3	248	184	160	248	112	80	3
240	13	87	184	160	248	112	80	3
240	13	87	184	160	248	184	80	3
240	13	87	112	80	3	248	184	160
248	112	80	3	240	13	87	184	160
248	112	80	3	240	13	87	184	160
248	184	80	3	240	13	87	112	80
3	248	184	160	248	112	80	3	240
13	87	184	160	248	184	80	3	240
13	87	184	160	248	184	80	3	248
112	80	3	240	13	87	184	160	248
112	80	3	240	13	87	184	160	248
184	80	3	240	13	87	112	80	3
248	184	160	248	112	80	3	240	13
87	184	160	248	112	80	3	240	13
87	184	160	248	184	80	3	240	13
87	112	80	3	240	13	87	184	160
248	112	80	3	240	13	87	184	160

 

It's like it pretty routinely misses some bytes. Here's my code:

void setup() {
 // initialize serial:
 Serial.begin(9600);
 Serial1.begin(2400);
}

int count = 0;

void loop() {
if (Serial1.available()) {
	if (count == 9) {
		Serial.println(Serial1.read());
		count = 0;
	}
	else {
		Serial.print(Serial1.read());
		Serial.print("\t");
	}
	count += 1;
}
}

For your issue with the clock's airbag light the only way that I found a work around for it was to make a Y connector keeping the clock connection together and then jumping the wires out for what was needed.

Link to comment
Share on other sites
  • 4 weeks later...

Archived

This topic is now archived and is closed to further replies.

Go to topic listing


×
×
  • Create New...

Important Information

Terms of Use

  I accept