The A/C pushbutton control module (N22) has DTC memory and data output. The diagnostic trouble codes and data are displayed via the temperature 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).
		P83.40-2028-04

Preparations for DTC Readout 1. Review 11 , 12 , 14 , 15 , 20 , 21 , 22 , 31 , 32 , 41 2. Ignition: ON 3. Temperature selector . 4. Within 20 seconds press and simultaneously for more than 5 seconds. 5. The LED in flashes and the display reads . 6. Press repeatedly until all DTC's are displayed. Record each DTC as it is displayed. The current faults (refer to table) are displayed first, next, the intermittant failures (e.g. 45 °5) are displayed in the display window next to the symbol. ° will apppear after the last DTC is displayed. Press again, ( delete, erase) will be displayed. 7. To erase: Press and simultaneously for more than 5 seconds and the display shows "-- -". To cancel erase: By pressing the current faults will appear again. 8. Turn ignition OFF to end test. Due to instrument cluster (IC) serial interface K1, K2; DTC's may be stored in IC memory, therefore readout and erase DTC memory.

Diagnostic trouble code (DTC) N22	Possible cause	Test step/Remedy 1)
- -	No malfunction in system	-
	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
	Evaporator temperature sensor (B10/6)	23 5.0
	ECT sensor (B11/4 )	23 10.0
	Refrigerant pressure sensor (B12)	23 8.0
	Refrigerant temperature sensor (B12/1)	23 6.0
	Refrigerant fill	23 6.0 , 8.0
	Coolant circulation pump (M13)	23 18.0
	Automatic A/C monovalve (Y19)	23 19.0
	Electromagnetic clutch (A9k1)	23 21.0
	Idle speed increase	-
	AIR control module (N65/1)	23 16.0
	Serial interface K1	23 10.0
	Switchover valve block (15 connection multiplex) (Y11)	23 22.0
	Serial interface K2	23 23.0

1) Observe Preparation for Test, see 22 .