Volkswagen New Beetle. Manual - part 1831

 

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Volkswagen New Beetle. Manual - part 1831

 

 

Test Requirements 

Ensure all fuses are okay, battery voltage is at least 11.5 volts and fuel pump relay is okay. Ensure all electrical 
accessories are off and A/C is off. Ensure engine is mechanically sound. Ensure no exhaust system leaks exist. 
Ensure engine coolant temperature is at least 176°F (80°C). On vehicles with M/T, gear shifter must be in 
neutral with parking brake set. On vehicles with A/T, selector lever must be in park or neutral with parking 
brake set.  

Test Procedure 

1. Check air induction and secondary air injection system for leaks. If no air leaks are found, go to next step. 

If air leaks are found. Repair as necessary. After repairs, erase DTC memory. Verify repair. Test is 
complete. Perform ECM relearn procedure. See TEST DRIVE RELEARN PROCEDURE .  

2. Connect Scan Tool. See RETRIEVING DIAGNOSTIC TROUBLE CODES . Start engine and idle for 

two minutes. Following scan tool manufacturer's instructions, use scan tool to check upstream HO2S 
(G39) heater activation. Observe scan tool in upstream HO2S heater activation test mode. Heater 
actuation must switch, alternating from on to off. If HO2S heater remains in off mode, go to next step. If 
HO2S heater switches, alternating from on to off, go to next step, further testing is needed.  

3. Turn ignition off. Raise vehicle and remove HO2 sensors protective cover and disconnect upstream 

HO2S (G39) harness connector (Black 6-pin). See Fig. 14 .  

4. Using DVOM check resistance of heater circuit on HO2S. Connect DVOM between terminals No. 3 and 

4 of HO2S. See Fig. 21 . Resistance should be 2.5-10 ohms at room temperature. If resistance is okay, go 
to next step. If resistance is not okay, replace faulty HO2S. After repairs, erase DTC memory. Verify 
repair. Test is complete. Perform ECM relearn procedure. See TEST DRIVE RELEARN 
PROCEDURE 
.  

5. Start engine and idle. Check voltage supply to HO2S heater. Connect DVOM between terminals No. 3 of 

HO2S harness connector and ground. See Fig. 22 . Voltage should be 11.0-14.5 volts. If voltage is okay, 
go to next step. If voltage is not okay. Turn ignition off. Using DVOM check resistance of HO2S harness 
connector terminal No. 3 to fuel pump relay (J17) harness connector. See ENGINE PERFORMANCE in 
SYSTEM WIRING DIAGRAMS article in ELECTRICAL. Resistance should be a maximum of 1.5 
ohms. Repair as necessary. After repairs, erase DTC memory. Verify repair. Test is complete. Perform 
ECM relearn procedure. See TEST DRIVE RELEARN PROCEDURE .  

6. Using DVOM and scan tool, check activation and voltage of heater circuit on HO2S. Connect DVOM 

between terminals No. 3 and 4 of HO2S harness connector. See Fig. 22 . Reconnect scan tool. Start 
engine and idle. Following scan tool manufacturer's instructions, use scan tool to check HO2S (G39) 
heater activation. Observe scan tool in upstream HO2S heater circuit activation mode. Observe voltage on 
DVOM. When scan tool shows heater circuit activation On, voltage should be 11.5-14.5 volts. When scan 
tool shows heater circuit activation alternating from On to Off, voltage should alternate from 12-0 volts. 
Turn ignition off. If voltage and/or activation is not okay, go to next step. If voltage and activation are 
okay. Test is complete. Perform ECM relearn procedure. See TEST DRIVE RELEARN 
PROCEDURE 
.  

7.  

wiring, power and ground supplies are okay. See ENGINE PERFORMANCE in 
SYSTEM WIRING DIAGRAMS article in ELECTRICAL and ECM GROUND & 
VOLTAGE SUPPLY . 

 

2003 Volkswagen New Beetle GLS 

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

  

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Disconnect ECM harness connector, leave ECM disconnected from test box. Connect Test Box (VAG 
1598/31) to ECM harness connector. See CONNECTING VAG TEST BOX . Using DVOM, check 
resistance between HO2S harness connector No. 4 and test box socket No. 5. See Fig. 22 . Resistance 
should be a maximum of 1.5 ohms.  

8. If resistance is not okay, repair as necessary. After repairs, erase DTC memory. Verify repair. Test is 

complete. Perform ECM relearn procedure. See TEST DRIVE RELEARN PROCEDURE . If 
resistance is okay, and all wiring is okay, replace faulty ECM. See ENGINE CONTROL MODULE 
REMOVAL & INSTALLATION 
. After repairs, erase DTC memory. Verify repair. Test is complete. 
Perform ECM relearn procedure. See TEST DRIVE RELEARN PROCEDURE .  

DTC P1117/17525 & P1118/17526: HO2S DOWNSTREAM TWC - HEATING CIRCUIT 

Code Definition 

DTC P1117/17525 
HO2 Sensor (G130) Downstream TWC - Heating Circuit Short To Ground 

DTC P1118/17526 
HO2 Sensor (G130) Downstream TWC - Heating Circuit Open  

Test Requirements 

Ensure all fuses are okay, battery voltage is at least 11.5 volts and fuel pump relay is okay. Ensure all electrical 
accessories are off and A/C is off. Ensure engine is mechanically sound. Ensure no exhaust system leaks exist. 
Ensure engine coolant temperature is at least 176°F (80°C). On vehicles with M/T, gear shifter must be in 
neutral with parking brake set. On vehicles with A/T, selector lever must be in park or neutral with parking 
brake set.  

Test Procedure 

1. Check air induction and secondary air injection system for leaks. If no air leaks are found, go to next step. 

If air leaks are found. Repair as necessary. After repairs, erase DTC memory. Verify repair. Test is 
complete. Perform ECM relearn procedure. See TEST DRIVE RELEARN PROCEDURE .  

2. Connect Scan Tool. See RETRIEVING DIAGNOSTIC TROUBLE CODES . Start engine and idle for 

two minutes. Following scan tool manufacturer's instructions, use scan tool to check downstream HO2S 
(G130) heater activation. Observe scan tool in downstream HO2S heater activation test mode. Heater 
actuation must switch, alternating from on to off. If HO2S heater remains in off mode, go to next step. If 

NOTE:

Before replacing ECM check HO2S control signal. See DTC P0170/16554, 
DTC P0171/16555 & DTC P0172/16556 . If HO2S control signal is not within 
specifications it may set a DTC for HO2S heater malfunction. 

NOTE:

If a test ends with ECM replacement, before replacing ECM be certain that, all 
wiring, power and ground supplies are okay. See ENGINE PERFORMANCE in 
SYSTEM WIRING DIAGRAMS article in ELECTRICAL and ECM GROUND & 
VOLTAGE SUPPLY . 

 

2003 Volkswagen New Beetle GLS 

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

  

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HO2S heater switches, alternating from on to off, go to next step (further testing is needed).  

3. Turn ignition off. Raise vehicle and remove HO2 sensors protective cover and disconnect downstream 

HO2S (G130) harness connector (Brown 4-pin). See Fig. 14 .  

4.  

Using DVOM check heater circuit on HO2S for continuity. Connect DVOM between terminals No. 1 and 
2 of HO2S. See Fig. 15 . HO2S heater circuit should have continuity. If HO2S heater circuit has 
continuity, go to next step. If HO2S heater circuit is open, replace faulty downstream HO2S. After 
repairs, erase DTC memory. Verify repair. Test is complete. Perform ECM relearn procedure. See TEST 
DRIVE RELEARN PROCEDURE 
.  

5. Start engine and idle. Check voltage supply to HO2S heater. Connect DVOM between terminal No. 1 of 

HO2S harness connector and ground. See Fig. 16 . Voltage should be 11.0-14.5 volts. If voltage is okay, 
go to next step. If voltage is not okay. Turn ignition off. Using DVOM check resistance of HO2S harness 
connector terminal No. 1 to fuel pump relay (J17) harness connector. See ENGINE PERFORMANCE in 
SYSTEM WIRING DIAGRAMS article in ELECTRICAL. Resistance should be a maximum of 1.5 
ohms. Repair as necessary. After repairs, erase DTC memory. Verify repair. Test is complete. Perform 
ECM relearn procedure. See TEST DRIVE RELEARN PROCEDURE .  

6. Using DVOM and scan tool, check activation and voltage of heater circuit on HO2S. Connect DVOM 

between terminals No. 1 and 2 of HO2S harness connector. See Fig. 16 . Reconnect scan tool (if 
removed). Start engine and idle. Following scan tool manufacturer's instructions, use scan tool to check 
HO2S (G130) heater activation. Observe scan tool in downstream HO2S heater circuit activation mode. 
Observe voltage on DVOM. When scan tool shows heater circuit activation On, voltage should be 11.5-
14.5 volts. When scan tool shows heater circuit activation alternating from On to Off, voltage should 
alternate from 12-0 volts. Turn ignition off. If voltage and/or activation is not okay, go to next step. If 
voltage and activation are okay. Test is complete. Perform ECM relearn procedure. See TEST DRIVE 
RELEARN PROCEDURE 
.  

7.  

Disconnect ECM harness connector, leave ECM disconnected from test box. Connect Test Box (VAG 
1598/31) to ECM harness connector. See CONNECTING VAG TEST BOX . Using DVOM, check 
resistance between HO2S harness connector No. 2 and test box socket No. 63. See Fig. 16 . Resistance 
should be a maximum of 1.5 ohms. If resistance is not okay, repair as necessary. After repairs, erase DTC 
memory. Verify repair. Test is complete. Perform ECM relearn procedure. See TEST DRIVE 
RELEARN PROCEDURE 
.  

8. If resistance is okay, and all wiring is okay, replace faulty ECM. See ENGINE CONTROL MODULE 

REMOVAL & INSTALLATION . After repairs, erase DTC memory. Verify repair. Test is complete. 
Perform ECM relearn procedure. See TEST DRIVE RELEARN PROCEDURE .  

DTC P1141/17549, P1142/17550 & P1143/17551: LOAD DETECTION

NOTE:

No resistance specification for HO2S heater circuit is given by 
manufacturer. 

NOTE:

Before replacing ECM check HO2S control signal. See DTC P0136/16520, 
DTC P0137/16521 & DTC P0138/16522 . If HO2S control signal is not within 
specifications it may set a DTC for HO2S heater malfunction. 

 

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 8:49:58 AM

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Code Definition 

DTC P1141/17549 
Load Detection - Implausible Value 

DTC P1142/17550 
Lower Limit Not Reached 

DTC P1143/17551 
Load Detection - Upper Limit Exceeded  

Test Requirements 

Ensure all fuses are okay, battery voltage is at least 11.5 volts, fuel pump relay must be okay, all electrical 
accessories are off and A/C is off. Ensure no exhaust system leaks exist. Verify engine is mechanically sound 
and engine coolant temperature is at least 176°F (80°C). On vehicles with M/T, gear shifter must be in neutral 
with parking brake set. On vehicles with A/T, selector lever must be in park or neutral with parking brake set.  

Test Procedure 

1. Inspect air induction system for leaks. Check air filter for blockage. Repair as necessary. After repairs, 

erase DTC memory. Verify repair. Test is complete. Perform ECM relearn procedure. See TEST DRIVE 
RELEARN PROCEDURE 
.  

2. Connect scan tool. See RETRIEVING DIAGNOSTIC TROUBLE CODES . Start engine and idle. 

Using scan tool, check air mass drawn in by engine. Air mass should be 2.0-5.0 grams/second at idle. If 
air mass reading is okay, go to next step (voltage supply for MAF sensor must be checked). If air mass 
reading is not okay, go to step 6 .  

3. Turn ignition off. Disconnect MAF sensor 5-pin connector. Using DVOM, measure voltage between 

MAF sensor 5-pin connector, terminal No. 2 and ground. See Fig. 18 . Start engine and idle. Voltage 
should be 11-15 volts. If voltage is okay, go to step 5 . If voltage is not okay, go to next step.  

4. Turn ignition off. Repair wiring from MAF sensor 5-pin connector, terminal No. 2 and fuel pump relay 

(J17). See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. 
After repairs, erase DTC memory. Verify repair. Test is complete. Perform ECM relearn procedure. See 
TEST DRIVE RELEARN PROCEDURE .  

5. Turn ignition on. Using DVOM, check voltage between MAF sensor 5-pin harness connector, terminal 

No. 4 and ground. See Fig. 18 . Voltage should be 4.5-5.5 volts. If voltage is okay, go to next step 
(further circuit tests are required). If voltage is not okay, go to next step.  

6. Turn ignition off. Disconnect ECM harness connector, leave ECM disconnected from test box. Connect 

Test Box (VAG 1598/31) to ECM harness connector. See CONNECTING VAG TEST BOX . Using 
DVOM, check resistance between the following MAF sensor (G70) harness connector terminals and test 
box sockets. See Fig. 18 . 

z

MAF sensor harness connector terminal No. 3 and test box socket No. 27.  

z

MAF sensor harness connector terminal No. 4 and test box socket No. 53.  

z

MAF sensor harness connector terminal No. 5 and test box socket No. 29.  

Resistance should be a maximum of 1.5 ohms for each reading. If resistance measurements are okay, go 

 

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 8:49:58 AM

Page 127 

© 2004 Mitchell Repair Information Company, LLC. 

 

 

 

 

 

 

 

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