The A/C pushbutton control module (N22) has DTC memory and data output. The diagnostic trouble codes and data are displayed via the display window. The stored DTC's will remain in memory even with the vehicle battery disconnected. The DTC memory differentiates between current and intermittent faults. All DTC's can also be read with the Hand-Held Tester (HHT). Connect HHT as indicted in section 0.
		P83.40-0304-01

Preparation for Test 1. Ignition: ON 2. Left display " ", right display " ". 3. Within 20 secs., press and simultaneously for > 5 secs. 4. The LED in flashes and the display window reads . 5. Press right > 1 sec. If there are no DTC's: is displayed in the left side of the display window and is displayed in the right side. If DTC's are stored in memory: is displayed in the left side of the display window and the DTC (e.g. ) is displayed in the right side (record each DTC as it is displayed). 6. Each malfunction (short circuit, open circuit, etc.) has a specific DTC (the DTC is displayed in the right side of the display window, is displayed in the left side). By pressing the next DTC is displayed (see table). 7. To Erase: (all DTC's must first be read out) press right and left > 2 secs., will be displayed in the left side of the display window and in the right side. To cancel erase: press right , the current faults will appear again (compare to DTC readout recorded earlier). Delete DTC's as often as necesarry until is displayed in the left side of the display window and is displayed in the right side. 8. Set temperature selector to normal setting. 9. Ignition OFF to end test.

Display code in N22 window		Possible cause	Test step/Remedy 1)
	-	No malfunction in system	-
		CAN communication with rear A/C	Wiring
		In-car temperature sensor (B10/4)	23 4.0
		Outside temperature indicator temperature sensor (B14)	23 10.0
		Left heater core temperature sensor (B10/2)	23 7.0
		Right heater core temperature sensor (B10/3)	23 8.0
		Evaporator temperature sensor (B10/6)	23 5.0
		ECT sensor (DFI, IFI) (B11/4)	23 9.0
		Refrigerant pressure sensor (B12)	23 11.0
		Refrigerant temperature sensor (B12/1)	23 6.0
		Sun sensor (B32)	23 12.0
		Emissions sensor (B31)	23 14.0
		Refrigerant fill	23 6.0 , 11.0
		Coolant circulation pump (A31m1)	23 17.0
		Left-side water valve (Y21y1)	23 18.0
		Right-side water valve (Y21y2)	23 18.0
		Electromagnetic clutch (A9k1)	23 21.0
		Idle speed increase	-
		AIR control module (N65/1)	23 15.0
		Serial interface (K1) to instrument cluster (A1)	23 30.0
		Switchover valve block (Y11)	23 20.0
		Activated charcoal filter actuator(A32m2) open	23 22.0
		Activated charcoal filter actuator (A32m2) closed	23 22.0
		Auxiliary heater-NON-USA (continue to next test step)	-
		Serial interface (K2) to instrument cluster (A1)	23 31.0
		LED - Center air outlet "Warm"	23 24.0
		LED - Center air outlet "Cold"	24 25.0
		Wide open throttle (WOT) position (diesel engines)	-

1) Observe Preparation for Test, see 22 .