Motronic injection and ignition system (2.0 ltr.
engine) Page 1 of 6
Evaluating measured value blocks, display groups 30...49, 107 -Lambda regulation-
Evaluating measured value blocks, display groups 30...49, 107 -Lambda regulation-
Display group 30 -Lambda regulation-
▪ Engine running at idling speed
Read measured value
block 30
⇒ ◂ Indicated on display
xxx xxx
1 2 3 4 ◂ Display zones Specification Evaluation
=> Page
Lambda regulation status after catalyst 110
01-99
=> Page
Lambda regulation status before catalyst 111
01-99
Notes on display zones 1 and 2:
l ◆ The Lambda probe heating may be switched on or off depending on the operating condition
of the engine, i.e. the 1st position in display zones 1 or 2 may show 1 or 0.
The 3rd position in display zone 2 is not set to 1 until in part throttle range.
Significance of figures in 3-digit number block, display zones 1 and 2 - status of Lambda regulation
before and after catalyst
Significance if display = 1
1 2 3
1 Lambda regulation active
1 Lambda probe operationally ready
1 Lambda probe heating on
Display group 32 -Lambda regulation- Lambda learnt values
▪ Engine running at idling speed
Read measured value
block 32
⇒ ◂ Indicated on display
xx.x % xx.x %
1 2 3 4 ◂ Display zones Specification Evaluation
=> Page
Lambda learnt value at part load (range 2) -10...10 %
01-101
=> Page
Lambda learnt value at idling speed (range 1) -10...10 %
01-101
Notes on display zones 1 and 2:
Low values indicate that the engine is running too rich and therefore the Lambda regulation is
leaning the mixture.
l ◆ High values indicate that the engine is running too lean and therefore the Lambda regulation
enriches the mixture.
l ◆ If there is no voltage supply to the control unit and the fault memory is erased, all the values
vw-wi://rl/V.en-GB.1J-MG-MGAZH.wi::45186135.xml?xsl=2 14.04.2023
Motronic injection and ignition system (2.0 ltr. engine) Page 2 of 6
learnt will be cancelled.
l ◆ Range 1 - The effects of the fault (e.g. unmetered air) decrease as the engine speed
increases. The injection period is modified by a fixed amount by this learnt value. This amount
is not dependent upon the basic injection period.
l ◆ Range 2 - The effects of the fault (e.g. faulty injector) increase as the engine speed
increases. This learnt value effects the injection period proportionally. This change is
dependent on the basic injection period.
Initiating learning process: Control unit in mode 04, Basic settings
l ◆ Learning conditions for idling: Idling, coolant temperature min. 75 °C, intake air
temperature max. 90 °C
l ◆ Learning conditions for part load: coolant temperature min. 75 °C, intake air temperature
max. 90 °C
Evaluating display zone 32, display zones 1 and 2 - Lambda learnt values
Appears on display Possible fault cause Fault elimination
- Low learnt values at idling
but with normal learnt values
- Disappears after motorway
Low Lambda learnt values at part throttle: possible oil
drive or oil change
dilution (high level of fuel in
oil)
- Check injector =>Page 24-
- Injector leaking
64
- Check fuel pressure
- Fuel pressure too high regulator and holding pressure
=> Page 24-73
- Check activated charcoal
- Activated charcoal filter
filter solenoid valve 1 =>
solenoid valve 1 permanently
Page 01-56 , Final control
open
diagnosis
- Check air mass meter =>
- Air mass meter defective
Page 24-33
- Lambda probe heating - Check Lambda probe
defective or Lambda probe heating
soiled =>Page 24-23
Appears on display Possible fault cause Fault elimination
- High learnt values at idling
speed, not so high learnt values - Check intake air system for
High Lambda learnt values at part throttle: possible leaks
unmetered air in area of intake =>Page 24-77
manifold
- Unmetered air between air
- Rectify cause
mass meter and throttle valve
- Check quantity injected rate
- Injector blocked
=>Page 24-64
- Display zones 1 and 2 high: - Check air mass meter =>
Air mass meter defective Page 24-33
- Check fuel pressure
- Fuel pressure too low regulator and holding pressure
=> Page 24-73
vw-wi://rl/V.en-GB.1J-MG-MGAZH.wi::45186135.xml?xsl=2 14.04.2023
Motronic injection and ignition system (2.0 ltr. engine) Page 3 of 6
- Unmetered air at exhaust
manifold gasket
- Lambda probe heating - Check Lambda probe
defective or Lambda probe heating
soiled =>Page 24-23
Display group 33 -Lambda regulation- Lambda regulation values
▪ Engine running at idling speed
Read measured value
block 33
⇒ ◂ Indicated on display
x.xxx
xx.x %
V
1 2 3 4 ◂ Display zones Specification Evaluation
Lambda probe voltage, Lambda probe before
1.4...1.6 V ---
catalyst
=> Page
Lambda regulator before catalyst -10.0...10.0 %
01-104
Notes on display zone 1:
l ◆ The display must fluctuate around 0. If constant 0 is displayed, the Lambda regulation has
switched from regulation to control, because there is a fault in the Lambda regulation.
Interrogate fault memory => Page 01-17 .
Notes on display zone 2:
l ◆ The voltage signal "rich mixture (low level of residual oxygen)" is below 1.5 V.
l ◆ The voltage signal "lean mixture (high level of residual oxygen)" is above 1.5 V.
Evaluating display group 33, display zone 1 - Lambda regulator before catalyst
Appears on display Possible fault cause Fault elimination
- Minus range: Mixture too
rich, Lambda control weakens
mixture - Wait 30 seconds until the
Outside tolerance range
- Positive range: Mixture too display has stabilised
lean, Lambda control enriches
mixture
- Check intake system for
- Unmetered air leaks
=> Page 24-77
- Check injection rate =>
- Injector defective
Page 24-64
- Check Lambda learnt value
- Lambda learnt value on limit
in display group 32
Display group 34 -Lambda regulation- Lambda probe diagnosis before catalyst (ageing check)
▪ Vehicle stationary, brake depressed, engine running at increased idling speed
▪ Control unit in mode 04-Basic settings
Read measured value
block 34
⇒ ◂ Indicated on display
vw-wi://rl/V.en-GB.1J-MG-MGAZH.wi::45186135.xml?xsl=2 14.04.2023
Motronic injection and ignition system (2.0 ltr. engine) Page 4 of 6
xxxx xxx.x °
xx.xx Text
rpm C
1 2 3 4 ◂ Display zones Specification Evaluation
Result of Lambda probe
before catalyst age check
(test OFF/test ON/B1-P1 B1-P1 OK ---
OK / B1-P1 n.OK)
Dynamic factor Lambda probe
before catalyst --- ---
Catalyst temperature min. 350 °C ---
1300...2600
Engine speed ---
rpm
Note on display zone 2:
Value calculated from engine speed and engine load.
Note on display zone 4:
The control unit compares the adjustment frequency of the Lambda probes evaluation circuitry with
a specification stored in the control unit. If this value is not reached, the message: "B1-P1 n.OK" is
indicated in display zone 4.
Display group 36 -Lambda regulation- Operational readiness of probe after catalyst
▪ Vehicle stationary, brake depressed so that engine runs at increased idling speed 1300...2600
rpm
▪ Control unit in mode 04 Basic setting
Read measured value
block 36
⇒ ◂ Indicated on display
x.xxx xxx.x °
xx.xx Text
V C
1 2 3 4 ◂ Display zones Specification Evaluation
Result of Lambda probe
after catalyst check (test
OFF/test ON/B1-P1 OK / B1-S1 OK ---
B1-P1 n.OK)
Irrelevant
Catalyst temperature at least 350 °C ---
=> Page
Lambda probe voltage, Lambda probe after catalyst 0.100...0.900 V
01-107
Note:
It can take a few minutes until display jumps from "Test ON" to "B1-P2 OK".
Evaluating display group 36, display zone 3 - Lambda probe voltage, Lambda probe after catalyst
Appears on display Possible fault cause Fault elimination
Constant 1.100 V - Short to positive via:
- Lambda probe, probe wiring, - Check Lambda probe wiring
vw-wi://rl/V.en-GB.1J-MG-MGAZH.wi::45186135.xml?xsl=2 14.04.2023
Motronic injection and ignition system (2.0 ltr. engine) Page 5 of 6
earth wiring, engine control => Page 24-95
unit
- Open circuit via:
Constant between - Lambda probe, probe wiring,
0.400...0.500 V earth wiring, engine control
unit
- Short to earth via:
- Lambda probe, probe wiring,
Constant 0.000 V
earth wiring, engine control
unit
Display group 37 -Lambda regulation- Lambda probes
▪ Engine running at idling speed
▪ Control unit in mode 04-Basic settings
Read measured value
block 37
⇒ ◂ Indicated on display
x.xxx
xx.x % x.xxx Text
V
1 2 3 4 ◂ Display zones Specification Evaluation
Result (Test On / OFF /
Syst. OK / n.OK) Syst. OK
Delta, Lambda after catalyst ---
Lambda probe voltage, Lambda probe after => Page
catalyst 0.000...1.000 V 01-107
=> Page
Engine load 10...25 %
01-89
Display group 41 -Lambda regulation- Lambda probe heating
▪ Engine running at idling speed
Read measured value
block 41
⇒ ◂ Indicated on display
Text Text
1 2 3 4 ◂ Display zones Specification Evaluation
Lambda probe heating Htg.aC.ON
---
after catalyst Htg.aC.OFF
Htg.bC.ON
Lambda probe heating before catalyst ---
Htg.bC.OFF
Note:
The Lambda probe heating may be switched ON or OFF depending on the operating conditions of
the engine, therefore the display in display zone 2 or 4 may show "Htg.b(a)C.ON" or alternating
from "Htg.b(a)C.ON" to Htg.b(a)C.OFF".
Display group 46 -Lambda regulation- Catalyst diagnosis (conversion test)
▪ Vehicle stationary, engine is running between 2800...3200 rpm
▪ Control unit in mode 04-Basic settings
Read measured value
block 46
⇒ ◂ Indicated on display
vw-wi://rl/V.en-GB.1J-MG-MGAZH.wi::45186135.xml?xsl=2 14.04.2023
Motronic injection and ignition system (2.0 ltr. engine) Page 6 of 6
xxxx xxxx °
x.xx Text
rpm C
1 2 3 4 ◂ Display zones Specification Evaluation
Result of catalyst
conversion test (Test
OFF/test ON/Cat B1 Cat B1 OK ---
OK/Cat B1 n.OK)
Measured value of catalyst
0...1 ---
conversion
Catalyst temperature at least 350 °C ---
2800...3200
Engine speed ---
rpm
Display group 107 -Lambda regulation-
▪ Engine running at idling speed
▪ Control unit in mode 04-Basic settings
Read measured value
block 107
⇒ ◂ Indicated on display
xxxx
x.x % Text
rpm
1 2 3 4 ◂ Display zones Specification Evaluation
Result of diagnosis (Test
OFF/Test ON / Syst. OK /
Syst. OK ---
Syst. n.OK))
Lambda regulator -10.0...10.0 %
=> Page
Engine speed (idling speed) 790...890 rpm
01-79
vw-wi://rl/V.en-GB.1J-MG-MGAZH.wi::45186135.xml?xsl=2 14.04.2023
