HEC Instrument Diagnostics (99-04 Mustang)

[iRoush]

You're probably wondering what I'm talking about when I say HEC Diagnostics. Basically what this does is allow you to digitalize all of the read outs of your gauges! As well of course, give you the option to diagnose any errors your instrument cluster may be experiencing. Here's how to do it:

To Enter Diagnostic Mode:

1.) Hold down the odometer button for 5 seconds

2.) Turn the ignition switch to Run (so you hear the fuel pump prime) *do not turn the key to start*

3.) Continue to hold the odometer button down until you see in the odometer reading "test", now let go immediately.

4.) The gauges will now do a sweeping test and read "Gage" in the odometer.

5.) To choose your diagnostic readout just press the odometer button and cycle through the options. To see the options while the car is running now start the car.

Here are the readouts for the different gauges in diagnostic mode:

GAGE - Activates gauge sweep of all gauges, then displays present gauge values. Also carries out the checksum tests on ROM and EE. If the gauge sweep is inoperative, INSTALL a new instrument cluster.

All segments illuminated - Illuminates all odometer segments. If any odometer segment is inoperative INSTALL a new instrument cluster.

bulb - Illuminates all micro-controlled indicators and LEDs. Install a new indicator or LED as necessary.

r - Returns to normal operation of all micro-controlled indicators and LEDs and displays hexadecimal value for ROM level. (used when requesting assistance from the hotline). If alternating flashes for FAIL and ROM level are displayed, INSTALL a new in

EE - Displays the hexadecimal value for EE level (used when requesting assistance from hotline). If alternating flashes of FAIL and EE level are displayed replace instrument cluster.

dt - Displays hexadecimal coding of final manufacturing test date (used when requesting assistance from hotline).

dtc - Displays continuous DTC's in hexadecimal format. Pressing the SELECT/RESET button will display any DTCs stored before proceeding to the next step.

enG - Displays the English speed in MPH. Speedometer will indicate present speed within tolerances. Display will show 0 if input in not received. If input is invalid for one second or more, or if speed is 0.

m - Displays the metric speed data in kph. Speedometer will indicate present speed within tolerances. Display will show 0 if input in not received. If input is invalid for one second or more, or if speed is 0.

tAc - Displays the tachometer data received from the PCM via the SCP network within tolerances. Tachometer will indicate present RPM. Display will show 0 if input is no received, if input received is invalid for one second or more, or if engine RPM is 0

FUEL -Displays the code (0-255) for the fuel sender input to the HEC. The fuel gauge will display a filtered fuel level value. This filter will keep the pointer from moving suddenly or erratically.

255 open send +/- 0

232 full stop +/- 0

215 Full mark +/- 10

178 3/4 mark +/- 8

138 1/2 mark +/- 7

93 1/4 mark +/- 5

41 E mark +/- 4

54 Low Fuel (0-59)

0-18 short (0-20 max)

OIL - Displays the code (0-250) for the oil pressure switch input to the HEC. Oil pressure gauge will indicate present oil pressure. Normal oil pressure (greater than 6psi) will display a value between 000 and 176. A low oil pressure or an inoperative e

dEGC[b/] - Display of engine temperature in Degrees C input from cylinder head temperature sensor.

49 C "C" mark

60 C Normal band start

120 C Normal band end

-40 C No SCP message for 5 seconds

bAtt - Displays the code (0-255) for the battery voltage input to the HEC. Battery voltage gauge will indicate present battery voltage.

93-102 6.2-9.1 volts, low voltage

115-124 8.5-10.7 volts, Normal band start

215-225 15.8-18 volts, Norm band end

230-241 16.9-19.1 volts, high voltage

rhEo -Displays the present decimal rheostat dimming input, 0-255 (used when requesting assistance from the hotline)

rhi

Not Used

rhS

Not Used

rho

Not used.

Cr - Displays the current RUN/START sense input. Display will show -h for high input with the ignition switch in the START position and -L for low input with the ignition switch in the RUN position.

PA-PE7

not used.

GAGE - Repeats the display cycle

[330CubeGt]

Nice bit of info, only seen it done once but I forgot how the guy did it. Kinda wish had these gauges its a nice feature..

Heads up and ass kickin! Using Tapatalk 2

[Number Tew]

If you ever pull all the needles off, this helps figure out if they're right haha