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Key to Quick Reference Chart


Fault diagnosis chart for manual diagnosis, LH 2.2

Key to quick-reference chart


E1 = Main relay
E2 = Pump relay
E3 = Pressure switch
E4 = Temperature sensor (NTC resistor)
E5 = Throttle position switch
E6 = Injectors
E7 = Mass air flow sensor
E7A = Mass air flow sensor, hot wire (filament)
E7B = Burn-off
E7C = CO content, %
E7D = Fuel system basic setting (cars with catalytic converter)
E8 = Control module
E8A = Control module input signals
E8B = Control module signals to injectors
E8C = Fuel shut-off on starting
E8D = Full-load enrichment
E8E = Warm-up period
E9 = AC compressor
E10 = Oxygen (Lambda) sensor
B1 = Fuel system
B1A = Line pressure
B1B = Fuel pressure regulator
B1C = Residual pressure
B1D = Fuel pump delivery pressure
B1E = Fuel pump delivery flow
I1 = Leakage in induction system
I2 = Auxiliary air valve
M1 = Basic setting of throttle butterfly
M1A = Adjustment of idling speed (not cars with catalytic converter)
M1B = Adjustment of idling speed (cars with catalytic converter)
E = Electrical
B = Fuel
I = Induction
M = Mechanical: removing and fitting of constituent components