Instrument Cluster Calibration???
05-07-2010, 09:29 AM
#11
TECH SAVANT
Join Date: Dec 2006
Location: Saint Augustine, FL
Posts: 10,938
Thanks. My tuner told me he has seen many Saleens where the speedo/tach were off. Mine is a 2000. I guess when they change the cluster and/or gauges, they were not right on. My outside worry was the cluster had gone bad at one time and they swapped it for a GT cluster, reusing the Saleen gauges. The GT has a 120mph? speedometer with a different ratio than the Saleen and the Saleen tach goes up to 7k and I have seen some GTs with an 8k tach. If someone put my gauges in a GT cluster, could that account for the inaccuracy? Or, is it just an issue with the gauges as seen by my tuner? Don't know exactly what to make of it. A good thing is the computer is seeing accurate tach and speedo data.
V6's have a 120MPH/7kRPM speedometer and tach.
Also, you need to clear your head of this notion that there are some sort of "ratios" embedded in the instrument cluster and/or gauges--there isn't.
There nothing about the speedometer or tachometer displays, and the cluster as a whole, that is calibrated to any engine, transmission, or rear-end specifics.
The cluster microcontroller receives digital messages over SCP bus that tell it what the engine and vehicle speeds are, in RPM and km/H--this is why using the HEC diag mode is showing accurate information. The cluster controller then drives the analog gauge servo motors so as to display a representation of the digital value.
All 6 gauges use the same servo motor:
The cluster controller is configured to match the gauges overlays, so that in a V6 cluster "full sweep" of the gauge will be 0-120 MPH, and 0-7k RPM; and 0-150MPH/0-8k on the V8 cluster. Swapping a V6 controller printed circuit onto a V8 overlay panel would result in grossly incorrect readings, as would using a V8 circuit board with the V6 gauge faces.
I don't know what you mean by someone putting your "gauges in a GT cluster"? If by "gauges" you mean the assembly shown above , and by "cluster" you mean the printed circuit board (which I can't find a photo of), then it would depend on the gauge faces what would be indicated.
The gauges have "no idea" what vehicle or engine speed they are displaying--all they know is that they are being told to move to 1/4, 1/2, full sweep or whatever. You could put a piece of paper on the gauge face that said 300 MPH at the 12 o'clock position and at 80 in a GT the speedometer would "say" 300 mile per hour.
Swapping the entire instrument cluster assembly, with the electronics, would require swapping the matching PCM too, or having a Ford dealer "remarry" the PCM and cluster electronics.
The PATS uses a shared security ID that is loaded into the cluster controller and the PCM at the factory, effectively marrying the two computers--if either component is changed with "re-marrying" then the engine will not start.
So I believe the short version of this story is that the indicator needles are incorrectly placed...
05-07-2010, 02:33 PM
#12
4th Gear Member
Join Date: Aug 2007
Location: Shelbyville, Indiana
Posts: 1,088
If the odometer in diagnostic mode is correct then it kind of sounds to me like someone put in an aftermarket overlay and didn't get the needles in the right place. The previous owner put one in my car. The tach was pretty close but speedometer was off 7 mph regardless of the speed. I found out that you have to have the wheels turning to get the speedometer needle back on correctly.
You may have to pull the needles and put them back on.
You may have to pull the needles and put them back on.
05-07-2010, 06:15 PM
#13
2nd Gear Member
Thread Starter
Join Date: Apr 2007
Location: MA
Posts: 219
If the odometer in diagnostic mode is correct then it kind of sounds to me like someone put in an aftermarket overlay and didn't get the needles in the right place. The previous owner put one in my car. The tach was pretty close but speedometer was off 7 mph regardless of the speed. I found out that you have to have the wheels turning to get the speedometer needle back on correctly.
You may have to pull the needles and put them back on.
You may have to pull the needles and put them back on.
05-07-2010, 06:18 PM
#14
2nd Gear Member
Thread Starter
Join Date: Apr 2007
Location: MA
Posts: 219
New-edge GTs have 150 MPH speedometers, and 8k tachs:
V6's have a 120MPH/7kRPM speedometer and tach.
Also, you need to clear your head of this notion that there are some sort of "ratios" embedded in the instrument cluster and/or gauges--there isn't.
There nothing about the speedometer or tachometer displays, and the cluster as a whole, that is calibrated to any engine, transmission, or rear-end specifics.
The cluster microcontroller receives digital messages over SCP bus that tell it what the engine and vehicle speeds are, in RPM and km/H--this is why using the HEC diag mode is showing accurate information. The cluster controller then drives the analog gauge servo motors so as to display a representation of the digital value.
All 6 gauges use the same servo motor:
The cluster controller is configured to match the gauges overlays, so that in a V6 cluster "full sweep" of the gauge will be 0-120 MPH, and 0-7k RPM; and 0-150MPH/0-8k on the V8 cluster. Swapping a V6 controller printed circuit onto a V8 overlay panel would result in grossly incorrect readings, as would using a V8 circuit board with the V6 gauge faces.
I don't know what you mean by someone putting your "gauges in a GT cluster"? If by "gauges" you mean the assembly shown above , and by "cluster" you mean the printed circuit board (which I can't find a photo of), then it would depend on the gauge faces what would be indicated.
The gauges have "no idea" what vehicle or engine speed they are displaying--all they know is that they are being told to move to 1/4, 1/2, full sweep or whatever. You could put a piece of paper on the gauge face that said 300 MPH at the 12 o'clock position and at 80 in a GT the speedometer would "say" 300 mile per hour.
Swapping the entire instrument cluster assembly, with the electronics, would require swapping the matching PCM too, or having a Ford dealer "remarry" the PCM and cluster electronics.
The PATS uses a shared security ID that is loaded into the cluster controller and the PCM at the factory, effectively marrying the two computers--if either component is changed with "re-marrying" then the engine will not start.
So I believe the short version of this story is that the indicator needles are incorrectly placed...
V6's have a 120MPH/7kRPM speedometer and tach.
Also, you need to clear your head of this notion that there are some sort of "ratios" embedded in the instrument cluster and/or gauges--there isn't.
There nothing about the speedometer or tachometer displays, and the cluster as a whole, that is calibrated to any engine, transmission, or rear-end specifics.
The cluster microcontroller receives digital messages over SCP bus that tell it what the engine and vehicle speeds are, in RPM and km/H--this is why using the HEC diag mode is showing accurate information. The cluster controller then drives the analog gauge servo motors so as to display a representation of the digital value.
All 6 gauges use the same servo motor:
The cluster controller is configured to match the gauges overlays, so that in a V6 cluster "full sweep" of the gauge will be 0-120 MPH, and 0-7k RPM; and 0-150MPH/0-8k on the V8 cluster. Swapping a V6 controller printed circuit onto a V8 overlay panel would result in grossly incorrect readings, as would using a V8 circuit board with the V6 gauge faces.
I don't know what you mean by someone putting your "gauges in a GT cluster"? If by "gauges" you mean the assembly shown above , and by "cluster" you mean the printed circuit board (which I can't find a photo of), then it would depend on the gauge faces what would be indicated.
The gauges have "no idea" what vehicle or engine speed they are displaying--all they know is that they are being told to move to 1/4, 1/2, full sweep or whatever. You could put a piece of paper on the gauge face that said 300 MPH at the 12 o'clock position and at 80 in a GT the speedometer would "say" 300 mile per hour.
Swapping the entire instrument cluster assembly, with the electronics, would require swapping the matching PCM too, or having a Ford dealer "remarry" the PCM and cluster electronics.
The PATS uses a shared security ID that is loaded into the cluster controller and the PCM at the factory, effectively marrying the two computers--if either component is changed with "re-marrying" then the engine will not start.
So I believe the short version of this story is that the indicator needles are incorrectly placed...
Maybe Saleen did not change the micro controller when they installed the Saleen gauges?
Last edited by apicia; 05-07-2010 at 07:10 PM.
05-10-2010, 06:09 PM
#15
2nd Gear Member
Thread Starter
Join Date: Apr 2007
Location: MA
Posts: 219
Saleen flashed the cluster with firmware to support the gauges that Simco produced for them. The new gauges have 200mph speedos and 7k tachs. Saleen is no longer offering any type of support for the pre-05 Saleens. If an owner of on 04 Saleen has a cluster go bad on them, Saleen tells Ford to install a GT cluster. Not a reasonable fix imo.
Saleen claims the tool they used to flash the firmware on the cluster is broken and they don't intend on fixing it. I asked for the firmware, so that I could have it flashed... they said no. Basically what I have is a bad cluster. I need a new cluster, flashed with Saleen calibration, and remarried to the PCM by Ford. Easy? Not. Saleen does not offer Ford the ability to get the correct firmware on a replacement cluster.
Saleen claims the tool they used to flash the firmware on the cluster is broken and they don't intend on fixing it. I asked for the firmware, so that I could have it flashed... they said no. Basically what I have is a bad cluster. I need a new cluster, flashed with Saleen calibration, and remarried to the PCM by Ford. Easy? Not. Saleen does not offer Ford the ability to get the correct firmware on a replacement cluster.
05-10-2010, 06:30 PM
#16
TECH SAVANT
Join Date: Dec 2006
Location: Saint Augustine, FL
Posts: 10,938
Saleen flashed the cluster with firmware to support the gauges that Simco produced for them. The new gauges have 200mph speedos and 7k tachs. Saleen is no longer offering any type of support for the pre-05 Saleens. If an owner of on 04 Saleen has a cluster go bad on them, Saleen tells Ford to install a GT cluster. Not a reasonable fix imo.
Saleen claims the tool they used to flash the firmware on the cluster is broken and they don't intend on fixing it. I asked for the firmware, so that I could have it flashed... they said no. Basically what I have is a bad cluster. I need a new cluster, flashed with Saleen calibration, and remarried to the PCM by Ford. Easy? Not. Saleen does not offer Ford the ability to get the correct firmware on a replacement cluster.
Saleen claims the tool they used to flash the firmware on the cluster is broken and they don't intend on fixing it. I asked for the firmware, so that I could have it flashed... they said no. Basically what I have is a bad cluster. I need a new cluster, flashed with Saleen calibration, and remarried to the PCM by Ford. Easy? Not. Saleen does not offer Ford the ability to get the correct firmware on a replacement cluster.
Sounds like a good reason to not buy a Saleen too--SOBs could have at least given you the firmware, since they apparently no longer have any proprietary use for it...
05-11-2010, 06:20 PM
#17
2nd Gear Member
Thread Starter
Join Date: Apr 2007
Location: MA
Posts: 219
Update. MJ has the device used to flash the cluster to Saleen specs. It has been broken since 2007. They see no need/reason to get it fixed. I guess Saleen owners whose cluster goes bad have no solution. They are screwed and are told to install a GT cluster.
05-12-2010, 09:37 PM
#18
2nd Gear Member
Thread Starter
Join Date: Apr 2007
Location: MA
Posts: 219
cliffyk, any pics of the micro controller? We need to find out if they use different micro controllers for the V6, GT, Cobra, etc. Or, do they use the same micro controller flashed to work with the values on the module (gauges).
05-13-2010, 08:55 AM
#19
TECH SAVANT
Join Date: Dec 2006
Location: Saint Augustine, FL
Posts: 10,938
I would think that it might be an FPGA device, however with Ford's purchasing power who knows?
05-13-2010, 09:22 AM
#20
2nd Gear Member
Thread Starter
Join Date: Apr 2007
Location: MA
Posts: 219
IF Ford used an FPGA device to control the module (gauges), then it should be flashable through the OBDII port. I have heard differing information about where Saleen plugged their device into to flash the micro controller.