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Scott.Boyd

01-18-2008, 09:39 AM

CarlD

01-18-2008, 07:34 PM

I've got a 2005 F150 V6 Automatic and I've entered a bunch of the XGauges described at the SG website.

I've checked my Mode and it shows CANSF.

CTQ and OSS seem to work fine. GR is displaying hex in gauge mode.

I've entered:

TXD 07E022163B
RXF 04620516063B
RXD 3010
MTH 000100010000

In park from idle to WOT it displays -164, at least its constant as it should be for a vehicle not in motion, same reading in D but stopped.

Locked in 1st at 15 MPH steady flat road it displays -2A92, more or less it does fluctuate, I'm guessing torque converter slipping.

Shifted up into 2nd at 15MPH steady flat road it displays 9580, more or less it does fluctuate, I'm guessing torque converter slipping.

I'm novice to all this HEX stuff and sending and receiving data, I'm guessing it is a math problem? :(

Any suggestions.

Thank you,

Try changing the "06" in the RXF to "86" to get hex readings and compare with what it displayed before. Let us know what is displayed.

You could also try using the CMNDS feature to look at the raw hex data. It does sound like there is something odd going on. In a memory in the CMNDS, enter 22163B, hit send and look at what comes back. Sometimes Ford makes the upper byte "FF" when the PID doesn't give valid data. Also, funny results can happen if the data location and size are not correct. Sending 22163B in the CMNDS will show what the data size is. The response should be 62163Bxxxx based on the RXD entry above. If it comes back 62163Bxx, you need to change the RXD to 3008. Sending 24FF163B will report the scaling and offset if your vehicle supports mode 24 for that PID.

Scott.Boyd

01-20-2008, 03:28 PM

CarlD

01-20-2008, 06:16 PM

Carl,

In the order you suggested:

Changed the 06 to 86 in RXF, no change to what was displayed. So I changed it back to 06.
Sent 22163B with CMNDS feature and got back 62163BFF5C00000000
Sent 24FF163B and got a blank screen, just the lower right OK button display.
Changed the RXD from 3010 to 3008 and now I get more sensible displays

Park or In Gear Stopped 255
1st Gear 181
2nd Gear 99
3rd Gear 63
4th Gear 44

Very little drift in these displayed numbers, display changes when I hear the shift points and remain constant with speed and rpm in the gear.

I have the 4R70E 4 speed automatic and it has these ratios:

1st 2.84:1
2nd 1.55:1
3rd 1:1
4th .7:1 overdrive
2.32:1 reverse

If we divide all the display values above by 63 (the value displayed for 3rd gear which is 1:1) you get pretty much the gear ratios of the transmission as specified by Ford.

I thought it would be as simple as changing the MTH

from 000100010000
to 000100400000 (divide by 64)

but that just gave me

Park or In Gear Stopped 63
1st Gear 45
2nd Gear 24
3rd Gear 15 or 16
4th Gear 11

again if we divide by the displayed 3rd gear value you get pretty much the ratios we expect.

I'm learning, but I have a long way to go :confused:

Can you help me understand what's going on?

Very good, it looks like the upper byte is FF like I suspected. Based on your results it looks like you might have the MTH at 000100040000 instead of 000100400000. It looks like your ratios divided by 4 instead of 64.

If we change the "05" in the RXF to "45", we can divide the value by 100. This should give two decimal places in the display. We can then multiply by 100 before the divide by 63.

So the MTH entry would be:

0064003F0000 multiply by 100 (hex 64), divide by 63 (hex 3F), and add 0. Then the result gets divided by 100.

TXD:07E022163B
RXF:04624516063B
RXD: 3008
MTH: 0064003F0000

See what this does. My neighbor across the street has an F150, but I don't know what year. If I see them I can try this stuff out also.

Good luck,

Carl

Scott.Boyd

01-20-2008, 10:17 PM

CarlD

01-20-2008, 10:45 PM

Carl,

You nailed it. I had fat fingered the MTH, I had:

0001|0004|0000 instead of 0001|0040|0000

Once I changed it to 0001|0040|0000 I got whole numbers in the display.

I entered your suggested:

TXD:07E022163B
RXF:04624516063B
RXD:3008
MTH:0064003F0000

And now my display is:

Park or in Gear Stopped 4.04
1st Gear 2.87 versus 2.84
2nd Gear 1.57 versus 1.55
3rd Gear 1.01 versus 1.00
4th Gear .69 versus .70

Very close to what we expect :woot:

Thank you Carl, that was fun.

I've been studying http://www.scangauge.com/support/OBDIITestStatus.shtml

and this XGAUGE Coding Information I found in another thread

http://www.cleanmpg.com/forums/showthread.php?p=65556

and page 24-29 of the Manual http://www.scangauge.com/support/pdfs/SGMan5_0.pdf

and your tutelage :)

If you or someone else has time I'd like to understand how each line is formatted. What I have so far:

TXD:07E0|22|163B Command to Transmit

07E0 ID for request, is this arbitrary or does it map to a particular Electronic Control Unit (ECU) on the CAN bus? Is this a hex number? Does it translate to a decimal number like 2016 or 7 224?

22 is the Mode this is non-legislated, could sometimes be 01 legislated (whatever that means)

163B is the Parameter Identification Number (PID) Is this a hex number? Does it translate to a decimal number?

RXF:04|62|45|16|06|3B Receive Filter (Tells us if this is our response or someone else's)

4 pairs, 1st member of pair is how many bytes in to look for a match that equals 2nd member of pair
04|62 says look 4 bytes in and find 62
45|16 says look 5 bytes in and find 16, the 4 in 45 is a special RXF feature that says the result of MTH will be divide by 100. If it had been 8 in 85 result of MTH gets divided by 10
06|3B says look 5 bytes in and find 3B

RXD:30|08 Data Location and Size

Two fields in HEX
30 says data we seek is HEX 30 = 48 Bits 48/8=6 Bytes into response
08 says data we seek is HEX 08 = 8 bits 8/8= 1 Byte long

MTH:0064|003F|0000 Scale and Offset to Apply to Response Before Displaying

Three fields of two bytes each 1st for multiply, 2nd for divide, 3rd for add/subtract in HEX
0064 means multiply by 100
003F means divide result by 63
0000 means add/subtract to result

If we sent 07E0|22|163B as the TXD of an X-Gauge and the truck is in 3rd gear, the displayed value is 1.01, what would the response we are interpreting look like in raw form if we could see it?

07|E0|22|62|16|3B|?? ???help???

Congrats Scott, you have an excellent grasp on everything! I'll have to mention to Ron at LL about the RXD entry for that GR add-a-gauge.

The 07E0 is the address for the ECU. The TCM is usually 07E1, but either seems to work. The original add-a-gauge did not have this feature, and the SG couldn't talk to the Escape Hybrid's battery computer. Ron added it and us FEH owners now have an incredibly more powerful tool in our quests for higher FE. There are some glitches being worked out due to the original processor being discontinued, but I'm sure Ron will figure everything out shortly.

The mode 01 or "legislated" PIDs are what the SG reads to get the original data items. If you look at the Wikipedia stuff for OBD-II PIDS there is a wealth of info, although some of it is incorrect. It also explains the mode 02, mode 03, mode 09 stuff. Sending 0902 in the CMNDS should return the VIN, but it has never worked in my FEH, although the 0906 CMNDS does return the vehicle calibration info.

If you want to play around to get an exact match for the GR, you could try a MTH of:

00C8 007F 0000 (multiply by 200 (00C8), divide by 127 (007F) and add 0 (0000)).

and see if it is closer. Maybe the original 64 divisor is closer than the 63 I gave.

The scientific calculator in Windows has Hex, Dec (default) ,Oct, and Bin formats available. It makes doing the coding a little simpler.

Carl

Scott.Boyd

01-21-2008, 12:13 PM

Carl,

Thank you for all the help. I'm going to summarize this thread here for posterity.

For a 2005 2WD Ford F150 with the 4R70E 4 speed automatic per Ford it has these ratios:

1st 2.84:1
2nd 1.55:1
3rd 1:1
4th .7:1 (overdrive)
Reverse 2.32:1

The SG is reporting MODE as CANSF

The published XGauge command on 21JAN08 at

http://www.scangauge.com/support/pdfs/XGAUGE.pdf

for a Ford CAN was:

TXD 07E022163B
RXF 04620516063B
RXD 3010
MTH 000100010000

this displayed nonsensical data.

The RXD was changed to 3008 and this produced

1st Gear 181
2nd Gear 99
3rd Gear 63
4th Gear 44

this at least showed the trend we expected. Finally we changed the RXF and MTH to massage the response into shape:

TXD:07E022163B
RXF:04624516063B (divide result by 100 for 2 decimal places (45))
RXD:3008 (take a smaller byte (08))
MTH:00C8007F0000 (multiply by 200 (00C8), divide by 127 (007F) and add 0 (0000) to scale it properly).

The display is now reporting:

ScanGauge vs Ford Spec
1st 2.85 vs 2.84
2nd 1.55 vs 1.55
3rd 0.99 vs 1.00
4th 0.69 vs 0.70
Rev 2.33 vs 2.32

This is as close as we could get it.

shifty35

01-21-2008, 01:58 PM

The variation is most likely due to tire diameter being slightly off, resulting in a speedometer that's slightly off. :)

Scott.Boyd

01-21-2008, 07:28 PM

Hi Ben,

I don't think the tire diameter would effect it. I think all the info to compute gear ratio (GR) is coming from the engine and transmission. I'm guessing what is being reported is RPM input to the transmission divided by Output Shaft Speed (OSS) which is another available PID on the CANSF. This doesn't compute the final drive ratio to the ground, just the ratio thru the transmission.

Regards,

shifty35

01-22-2008, 10:28 AM

Ah, if you have access to OSS, then the variation can only be due to roundoff error or somesuch in the software. Nice work!