Volkswagen New Beetle. Manual - part 1802

ELECTRONIC POWER CONTROL WARNING LIGHT (K132) 

Components that make up the EPC system are the ECM and EPC warning light. The Throttle Valve Drive 
(G186), Angle Sensor 1 for throttle valve drive (G187) and Angle Sensor 2 for throttle valve drive (G188) are 
an integral part of Throttle Valve Control Module (J338). The Accelerator Position Sensor 1 (G79) and 
Accelerator Position Sensor 2 (G185) are together in 1 unit and are located in accelerator pedal assembly.  

MIL and EPC warning light both illuminate when a system failure has been detected in the EPC system. DTC is 
also stored in ECM memory. For location of EPC warning light, see Fig. 2 and Fig. 3 .  

ELECTRONIC POWER CONTROL WARNING LIGHT CHECK 

Turn ignition on, with engine off. If EPC does not illuminate, check for codes. See RETRIEVING 
DIAGNOSTIC TROUBLE CODES , repair as necessary. If no DTCs are present, check wiring and 
instrument cluster for EPC. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in 
ELECTRICAL.  

If EPC is illuminated with engine running, turn engine off. Check for codes. See RETRIEVING 
DIAGNOSTIC TROUBLE CODES , repair as necessary. If no DTCs are present, check wiring and 
instrument cluster for EPC. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in 
ELECTRICAL.  

TESTING PROCEDURES 

Diagnosis of engine control system should be performed in the following order:  

1. Perform a visual inspection. See VISUAL INSPECTION article. Ensure all engine systems not related 

to ECM are operating properly. Check for any Technical Service Bulletins (TSBs) that may apply. DO 
NOT proceed with testing unless all engine problems not related to ECM have been repaired.  

2.  

Start engine and check MIL. If MIL flashes, this indicates malfunctions that may cause catalytic 
converter damage (e.g. misfire). If MIL flashes or stays on, enter diagnostics and determine if DTCs are 
present. See RETRIEVING DIAGNOSTIC TROUBLE CODES . If DTCs were displayed, determine 
whether codes are hard or sporadic malfunctions (intermittent codes). Hard codes will cause MIL to 
illuminate continuously while engine is running. See ON-BOARD DIAGNOSTICS .  

NOTE:

Electronic Power Control (EPC) is Volkswagen's name for their electronic 
throttle drive system. Also referred to as E-Gas System by Volkswagen. 

NOTE:

Instrument Cluster Control Module (J285) and Can Data Bus OBD Interface 
(J533) are integral parts of the instrument cluster. If instrument cluster is 
replaced, Can Data Bus OBD Interface (J533) must be coded. See CAN DATA 
BUS OBD INTERFACE (J533) CODING . 

NOTE:

Read and record DTCs before starting diagnostic work, (some testing 
procedures will set DTCs). 

 

2003 Volkswagen New Beetle GLS 

2001-2003 ENGINE PERFORMANCE Self-Diagnostics - 2.0L - Beetle, Golf & Jetta (Engine Codes AVH & AZG)

  

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3. For diagnosing hard codes, proceed to appropriate DTC test. See DIAGNOSTIC TROUBLE CODE 

IDENTIFICATION . When diagnosing sporadic malfunctions (intermittent codes), using Scan Tool 
VAG 1551/1552 or VAS 5051/5052 most sporadic malfunctions (intermittent codes) will display 
with /SP (sporadic malfunction) after code.  

4. If MIL stays on, and no DTCs are present, or if MIL does not come on, check MIL. See 

MALFUNCTION INDICATOR LIGHT CHECK .  

5. After necessary repairs are made, perform ECM test drive relearn procedure. See TEST DRIVE 

RELEARN PROCEDURE .  

VISUAL INSPECTION 

Prior to retrieving DTCs, perform a comprehensive visual inspection of underhood components. Check ground 
connections located on intake manifold, ground cable between engine and vehicle body and that battery cables 
are clean and tight. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in 
ELECTRICAL.  

Check vacuum hoses for breakage and blockage. Check electrical wiring and harness connectors for damage 
and corrosion. Repair as necessary. Ensure all engine systems not related to ECM are operating properly. Check 
for any Technical Service Bulletins (TSBs) that may apply. DO NOT proceed with testing unless all engine 
problems not related to ECM have been repaired. Go to step 2 under TESTING PROCEDURES.  

AUTOMATIC TEST SEQUENCE (FUNCTION 00) 

Generic Scan Tool 

Turn ignition off. Connect scan tool to diagnostic connector located under left side of dashboard. See Fig. 1 . 
Follow scan tool manufacturer instructions for entering AUTOMATIC TEST SEQUENCE.  

Scan Tool VAG 1551/1552 or VAS 5051/5052 

1. Turn ignition off. Connect scan tool to diagnostic connector located under left side of dashboard. See Fig. 

1 . To enter Automatic Test Sequence, press "0" key 2 times for address word "Automatic test sequence" 
and enter by pressing "Q" key. VAG 1551/1552 or VAS 5051/5052 communicates with all control 
modules in CAN Data Bus. Any DTCs that are stored will be displayed or "No DTC recognized" will 
display for each control module one after another. Automatic test sequence has ended when, "VAG On 
Board Diagnostic HELP 1 - Rapid data transfer 2 - Flash code output" is displayed. Erase DTCs. See 
CLEARING DIAGNOSTIC TROUBLE CODES . Perform test drive. See TEST DRIVE RELEARN 
PROCEDURE . Go to next step.  

2. If no DTCs are stored after test drive, press keys "0" and "6" for function "End Output" and enter by 

pressing "Q" key. If DTC(s) are stored in a control module in CAN Data Bus, see appropriate DTC table 

NOTE:

It is recommended that all control modules in the CAN Data Bus are checked for 
DTCs before starting and after performing DTC testing and repair work (during 
test and assembly work malfunctions can be recognized from other control 
modules like harness connector disconnected). Automatic Test Sequence is 
function 00 when using Scan Tool VAG 1551/1552 or VAS 5051/5052. 

 

2003 Volkswagen New Beetle GLS 

2001-2003 ENGINE PERFORMANCE Self-Diagnostics - 2.0L - Beetle, Golf & Jetta (Engine Codes AVH & AZG)

  

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and diagnostic procedure, (e.g. ABS DTC IDENTIFICATION table, under appropriate BRAKES/ANTI-
LOCK/TRACTION CONTROL article, if ABS DTC is stored). Repair as necessary. After repairs, erase 
DTC memory. Verify repair. Test is complete. Perform test drive. See TEST DRIVE RELEARN 
PROCEDURE .  

RETRIEVING DIAGNOSTIC TROUBLE CODES (FUNCTION 02) 

Generic Scan Tool 

Turn ignition off. Connect scan tool to diagnostic connector located under left side of dashboard. See Fig. 1 . 
Follow scan tool manufacturer instructions for reading DTCs. To identify DTCs, see DIAGNOSTIC 
TROUBLE CODE IDENTIFICATION . After performing DTC checks and repair work, malfunctions may 
be present in other control modules such as harness connector disconnected. DTC memories of all control 
modules must be checked and erased. See AUTOMATIC TEST SEQUENCE .  

Scan Tool VAG 1551/1552 Or VAS 5051/5052 

NOTE:

Read and record DTCs before starting diagnostic work, some testing 
procedures will set DTCs. If no DTCs are stored, do not erase memory, erasing 
DTC memory will cause readiness code to be erased. If ignition is switched off 
between "Retrieving Diagnostic Trouble Codes" and "Clearing Diagnostic 
Trouble Codes" the DTC memory will not be erased, repeat "Retrieving 
Diagnostic Trouble Codes" procedure. 

NOTE:

It is recommended that all control modules in the CAN Data Bus are checked for 
DTCs before starting and after performing DTC testing and repair work (during 
test and assembly work malfunctions can be recognized from other control 
modules like a harness connector disconnected). See AUTOMATIC TEST 
SEQUENCE . 

NOTE:

Manufacturer recommends use of Scan Tool VAG 1551/1552 or VAS 5051/5052. 
Generic scan tool may not be able to perform all test functions. If engine does 
not start, (this test requires using Scan Tool VAG 1551/1552 or VAS 5051/5052) 
connect scan tool. Operate starter for approximately 6 seconds, do not switch 
ignition off. Turn on scan tool printer. Operate scan tool, according to scan tool 
display information. Check for DTCs. 

NOTE:

When using Scan Tool VAG 1551/1552 or VAS 5051/5052, malfunctions which 
only occur sporadically (intermittently) will have the addendum sporadic 
(intermittent) malfunction on the print out and will be indicated on the display 
by the addendum /SP. Cause of sporadic malfunctions can be a loose harness 
connector or an intermittently open circuit. If a sporadic malfunction does not 
occur again within 40 warm-up phases, sporadic DTCs will be erased from ECM 
memory. A warm-up phase is engine started with coolant temperature below 
122°F (50°C), switched off at above 162°F (72°C). 

 

2003 Volkswagen New Beetle GLS 

2001-2003 ENGINE PERFORMANCE Self-Diagnostics - 2.0L - Beetle, Golf & Jetta (Engine Codes AVH & AZG)

  

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1. Connect scan tool to diagnostic connector located under left side of dashboard. See Fig. 1 . Start engine 

and idle.  

2. Using Scan Tool VAG 1551/1552 or VAS 5051/5052 start engine and press keys "0" and "1" for address 

word "Engine Electronics", press keys "0" and "2" for "Check DTC memory" and enter by pressing "Q" 
key. If DTCs are present, record or print DTCs. Press keys "0" and "5" for function "Erase DTC memory" 
and enter by pressing "Q" key. Press right arrow key, press keys "0" and "6" for function "End Output" 
and enter by pressing "Q" key. To identify DTCs, see DIAGNOSTIC TROUBLE CODE 
IDENTIFICATION . Repair as necessary. If no DTCs are present "No DTC recognized" will display. 
Press right arrow key, press keys "0" and "6" for function "End Output" and enter by pressing "Q" key.  

3. After performing DTC checks and repair work, malfunctions may be present in other control modules 

such as harness connector disconnected.  

4. DTC memories of all control modules must be checked and erased. This sequence when using Scan Tool 

VAG 1551/1552 or VAS 5051/5052. See AUTOMATIC TEST SEQUENCE .  

5. If no DTCs are present or after clearing diagnostic trouble codes from all control modules, perform a long 

road test. Coolant temperature needs to be greater than 176° F (80° C). Idle, partial throttle, full throttle 
and overdrive, must all be attained several times. During test drive, apply full throttle until engine speed 
exceeds 3500 RPM. After road test recheck all control modules for DTCs. If DTCs are present, repair as 
necessary. Clear codes. See CLEARING DIAGNOSTIC TROUBLE CODES . Verify repairs. Test is 
complete.  

CLEARING DIAGNOSTIC TROUBLE CODES (FUNCTION 05) 

Generic Scan Tool 

Turn ignition off. Connect scan tool to diagnostic connector located under left side of dashboard. See Fig. 1 . 
Follow scan tool manufacturer instructions for clearing DTCs.  

Scan Tool VAG 1551/1552 Or VAS 5051/5052 

Turn ignition off. Connect scan tool to diagnostic connector located under left side of dashboard. See Fig. 1 . 
DTCs must be read before being erased. See RETRIEVING DIAGNOSTIC TROUBLE CODES . If using 
Scan Tool VAG 1551/1552 or VAS 5051/5052 start engine Press keys "0" and "1" for address word "Engine 
Electronics", press keys "0" and "5" for function "Erase DTC memory," and enter by pressing "Q" key. Press 
keys "0" and "6" for function "End Output", and enter by pressing "Q" key. 

NOTE:

It is recommended that all control modules in the CAN Data Bus are checked for 
DTCs before starting and after performing DTC testing and repair work (during 
test and assembly work malfunctions can be recognized from other control 
modules like e.g. harness connector disconnected). See AUTOMATIC TEST 
SEQUENCE . 

NOTE:

If ignition is switched off between "Retrieving Diagnostic Trouble Codes" and 
"Clearing Diagnostic Trouble Codes" the DTC memory will not be erased, repeat 
"Retrieving Diagnostic Trouble Codes" procedure. 

 

2003 Volkswagen New Beetle GLS 

2001-2003 ENGINE PERFORMANCE Self-Diagnostics - 2.0L - Beetle, Golf & Jetta (Engine Codes AVH & AZG)

  

Helpmelearn Repair Manuals 

 

Wednesday, December 14, 2005 8:49:53 AM

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© 2004 Mitchell Repair Information Company, LLC.