[N*Caddy]

Here is something to check:

Enter in diagnose mode (Ignition ON – engine can be either on or off - and press and hold Pas Warmer & AC OFF until all dashboard lights and display elements will light up – IS OK don’t be alarm is just to test if working - it is called segment text).
Focus your attention to the IPC display strip (where you read your trip, the odometer and the messages like “Apply break to …”). The display will show some codes like “B1234 History”, or “NO RFA CODES” with a frequency of one every 2 – 3 seconds. Either wait until the display will show “PCM?” or just press FAN SPEED DOWN (i.e. NO) to skip the codes display sequence.

Here are some general instructions:
FAN SPEED DOWN = NO
FAN SPEED UP = YES
A/C OFF = EXIT CURRENT MENU
TURN IGNITION OFF = END ALL (you can do this at ANY time, say if you are lost)

Now let’s return…
When you see on the display “PCM?” press FAN SPEED DOWN (NO) to get to the next menu (“PCM?” means “Do you want to enter in the PCM menu?” and your answer is NO – FAN SPEED DOWN).
Press NO until the display will show “IPC?” witch in fact is the next menu after PCM (so you only need to press NO once. But should you accidentally pass the IPC menu NO biggie, just press NO until the “IPC?” menu will show up again. The menus are enumerated in a circular manner (once you got to the last one the first one is displayed as next). The menu sequence is: PCM, IPC, ACM, SIR, TCS, RSS, PZM, IRC, RFA, CCP, MSM, MMM, PHN (not all menus are available, some are options that may or may not equip your vehicle).
So you see “IPC?” on the screen ( i.e. “Do you want to enter in the IPC menu?” Your answer should be YES) press FAN SPEED UP to enter in the IPC menu.
Once in the IPC menu you will be prompted: “IPC CODES?”, “IPC DATA?”, IPC INPUTS?” “IPC OVERRIDES?”. Press NO (FAN SPEED DOWN) until “IPC OVERRIDES?”.
“IPC OVERRIDES?” press YES (FAN SPEED UP). And then press NO (FAN SPED DOWN) until IPS02 OPTION B. In 1-2 seconds the IPS02 value will be displayed where your trip odometer usually displays.
IF your speedometer is in miles the correct value you should read is 0 (ZERO), if in KM should read either 1 - Norway/Sweden, 2 - Canada, 4 – Saudi Arabia, 8 – Japan and 16 - Europe.
If it doesn’t match then change the value using the PAS WARMER - red (+1) and PAS COOLER – blue (-1).
Please MAKE SURE you only use the values mentioned above (or else you will need a new IPC). Once the proper value set press and HOLD the Front Defrost (Symbol) and A/C OFF buttons until the value flashes (in about 3 seconds).

Should you be lost at any point turn the ignition OFF and then start all over.
Once the value flashed it means it was STORED so you can turn the ignition OFF or press A/C OFF until you get to the beginning of the diagnose mode (i.e. the segment test), then while all lights are on press again A/C OFF to exit the diagnose mode.

You did mentioned you know how to put codes, but I posted the full procedure in case somebody else needs the same thing and does not know how to pull codes.