Volkswagen Golf / Golf GTI / Jetta. Manual - part 105

01-1

 

  

  

On Board Diagnostic (OBD) 

  

  

On Board Diagnostic (OBD) features

 

  

   The Motronic Engine Control Module (ECM) 

-J220- is equipped with a DTC memory.  

  

   If Diagnostic Trouble Codes (DTCs) occur in 

the sensors and components being 
monitored, they will be stored in the DTC 
memory together with an indication of the 
type of malfunction.  

  

   After evaluating the information the Motronic 

Engine Control Module (ECM) -J220- 
decides between the different Diagnostic 
Trouble Codes (DTCs) 

 DTC table from 

 

Page 01-30

 and stores these until the 

contents of the DTC memory are erased.  

  

   Diagnostic Trouble Codes (DTCs) which 

only occur sporadically will have the 
addendum "sporadic fault" on the print out. 
These Diagnostic Trouble Codes (DTCs) will 
be indicated on the display by the 
addendum "/SP". The cause of sporadic 
Diagnostic Trouble Codes (DTCs) can be 
e.g. a loose terminal or a brief open circuit. If 
a "sporadic malfunction" does not occur 
again within 40 warm-up phases (engine 
start below 50  C coolant temperature - 
switched off above 72  C), it will be erased 
from the DTC memory.  

  

   The Diagnostic Trouble Codes (DTCs) 

stored can be read-out with the VAG 1551 
scan tool, the vehicle system tester VAG 
1552 or the vehicle diagnostic, testing and 
information system VAS 5051 

 

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23

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On Board Diagnostic (OBD)

01-2

 

  

   The DTC memory must be erased after the 

malfunction(s) have been repaired 

 

Page 

01-23

 and the readiness code must be 

regenerated 

 

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   All Motronic Engine Control Module (ECM) -

J220- learned values will be erased when 
the Motronic Engine Control Module (ECM) 
-J220- connector is pulled off or the battery 
is disconnected. However the contents of 
the DTC memory are retained. When the 
engine is subsequently started the idling 
could be rough for a brief period. In this 
case leave the engine running for a few 
minutes at idle or perform a longer road test, 
until the learning process is completed. 
Procedure after voltage supply has been 
interrupted   

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   Note:  

  

   General information for On Board Diagnosis 

(OBD) can be found in the instruction 
manuals for the VAG 1551 scan tool, 
vehicle system tester VAG 1552 or VAS 
5051. 

On Board Diagnostic (OBD)

01-3

 

  

  

Electronic Power Control 
(EPC) Warning Light -K132-

 

  

  

"EPC" is the abbreviation for 
Electronic Power Control.  

     Location of Electronic Power Control 

(EPC) Warning Light -K132-  

When the ignition is switched on the 
Motronic Engine Control Module 
(ECM) -J220- checks all components 
which are important for the correct 
functioning of the Electronic Power 
Control.  

If malfunctions are detected in 
Electronic Power Control system 
when the engine is running, the 
Motronic Engine Control Module 
(ECM) -J220- will switch on the 
Electronic Power Control (EPC) 
Warning Light -K132-. (Diagnostic 
Trouble Codes (DTCs) are identified 
accordingly in the DTC table). 
Simultaneously an entry is made in 
the Motronic Engine Control Module 
(ECM) -J220- DTC memory.   

Functional check:  

If the Electronic Power Control 
(EPC) Warning Light -K132- does 
not light-up with ignition switched 
on:  

 

Repair Manual, Electrical 

Equipment On Board Diagnostic 
(OBD),Repair Group 01

 

-  Switch on ignition: 

   Electronic Power Control (EPC) 

Warning Light -K132- must light-
up. 

-  Check instrument cluster and 

Electronic Power Control (EPC) 
Warning Light -K132-: 

On Board Diagnostic (OBD)

01-4

 

  

   If the Electronic Power Control (EPC) Warning 

Light -K132- lights up with ignition switched on:  

  

  

-  Start engine and run at idle: 

  

  

   The Electronic Power Control (EPC) Warning 

Light -K132- must go out after several seconds. 

  

   If the Electronic Power Control (EPC) Warning 

Light -K132- does not go out:  

  

  

-  Check DTC memory, repair Diagnostic Trouble 

Codes (DTCs) if necessary and then erase DTC 
memory 

 

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 , DTC memory, checking 

and erasing. 

  

  

-  Read off readiness code 

 

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 . If the 

DTC memory has been erased or the Motronic 
Engine Control Module (ECM) -J220- was 
disconnected from battery (B+) positive, the 
readiness code must be generated again 

 

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On Board Diagnostic (OBD)