Audi A8/A8L/S8 Quick Reference Specification Book • September 2013 325

DTC Chart

DTC

DTC

Error Message

Malfunction Criteria and
Threshold Value

P12A6

Fuel Rail Pressure Sensor
High Pressure System

• Pressure control activity
< -0.06 MPa
and
• Fuel trim activity > 1.33
and
• Difference between target
pressure - actual pressure
-16.38 to 16.38 MPa

P12A7

Fuel Volume Regulator
Control

• Pressure control activity
< -4.0 MPa
• Fuel trim activity 0.75-1.25
• Difference between target
pressure - actual pressure
< -4.0 mPa

P129B

Fuel Pressure Regulator Valve • Signal voltage 1.40 to 3.20 V
Bank 2 Open Circuit
or
• Signal pattern incorrect

P129C

Fuel Pressure Regulator
Valve Bank 2 Short Circuit To
Ground

P129D

Fuel Pressure Regulator Valve Signal voltage > 3.20 V
Bank 2 Short Circuit To B+

P1321

Knock Control System Error

Short to ground Port B lower
threshold < -0.70 V
• Short to ground Port B lower
threshold < -0.70 V
Short to ground Port A lower
threshold < -0.70 V
• Si short to ground Port A lower
threshold < -0.70 V
Signal range check
• Signal range check lower
threshold < 0.7 to 3.0 V

P1322

Knock Control System Error

• Short to battery plus Port A
upper threshold > 1.00 V
• Signal range check upper
threshold > 44 to 116 V
• Short to battery plus Port B
upper threshold > 1.00 V
• Short to battery plus Port A
upper threshold > 1.00 V
• Signal range check upper
threshold > 69.00 to 116.16 V

Signal voltage 1.40 to 3.20 V

326 Audi A8/A8L/S8 Quick Reference Specification Book • September 2013

Error Message

Malfunction Criteria and
Threshold Value

P1323

Knock Control System Error

Short to ground Port B lower
threshold < -0.70 V
• Short to ground Port B lower
threshold < -0.70 V
Short to ground Port A lower
threshold < -0.70 V
• Short to ground Port A lower
threshold < -0.70 V
Signal range check
• Signal range check lower
threshold < 0.7 to 3.02V

P1324

Knock Sensor 4 - Signal Too
High

• Short to battery plus Port A
upper threshold > 1.00 V
• Signal range check upper
threshold > 44 to 116 V
• Short to battery plus Port B
upper threshold > 1.00 V
• Short to battery plus Port A
upper threshold > 1.00 V
• Signal range check upper
threshold > 69.00 to 116.16 V

P1489

Evaporative Emission System
Purge Control Valve Circuit
High

Signal current > 2.2 A

P1497

Secondary Air Injection
System Insufficient Flow Bank
3

• Relative secondary air mass
flow 80 %
and
• ECM power stage no failure
Rationality check
• Deviation throttle value angles
vs. calculated value > 4.00 50.00%

P2101

Throttle Actuator A Control
Motor Circuit Range/
Performance

Signal range check
• Duty cycle > 80%
and
• ECM power stage, no failure
Rationality check
• Deviation throttle valve angles
vs. calculated value 4.0 50.0%

P2106

Throttle Actuator Control
System - Forced Limited
Power

Internal check Failed

P2108

Throttle Actuator Control
System -Basic settings

Signal range check @
mechanical stop low
• TPS 1 signal voltage < 0.40;
> 0.8V
or
• TPS 2 signal voltage < 4.20;
> 4.6V

P2122

Throttle/Pedal Position
Sensor/Switch “D” Circuit Low
Input

Signal voltage < 0.65 V

P2123

Throttle/Pedal Position
Signal voltage > 4.79 V
Sensor/Switch “D” Circuit High
Input

P2127

Throttle/Pedal Position
Sensor/Switch “E” Circuit Low
Input

Signal voltage < 0.28 V

P2128

Throttle/Pedal Position
Sensor/Switch “E” Circuit High
Input

Signal voltage > 2.43 V

P2138

Throttle/Pedal Position
Sensor/Switch “D” / “E”
Voltage Correlation

Signal voltage sensor 1 vs.
sensor 2 > 0.14 - 0.70 V

328 Audi A8/A8L/S8 Quick Reference Specification Book • September 2013

Error Message

Malfunction Criteria and
Threshold Value

P2146

Fuel Injector Group “A” Supply Short to ground (high side)
Voltage Circuit/Open
• Signal current > 14.90 A
• Short to battery plus (high
side) signal current < 2.60 A
• Core connection (high side low side) signal current
< 2.60 A

P2149

Fuel Injector Group “B” Supply Short to ground (high side)
Voltage Circuit/Open
• Signal current > 14.90 A
• Short to battery plus (high
side) signal current < 2.60 A
• Core connection (high side low side) signal current
< 2.60 A

P2152

Fuel Injector Group “C” Supply Short to ground (high side)
Voltage Circuit/Open
• Signal current > 14.90 A
• Short to battery plus (high
side) signal current < 2.60 A
• Core connection (high side low side) signal current
< 2.60 A

P2155

Fuel Injector Group “D” Supply Short to ground (high side)
Voltage Circuit/Open
• Signal current > 14.90 A
• Short to battery plus (high
side) signal current < 2.60 A
• Core connection (high side low side) signal current
< 2.60 A

P216A

Fuel Injector Group “E” Supply Short to ground (high side)
Voltage Circuit/Open
• Signal current > 14.90 A
• Short to battery plus (high
side) signal current < 2.60 A
• Core connection (high side low side) signal current
< 2.60 A

P216D

Fuel Injector Group “F” Supply
Voltage Circuit/Open

Short to ground (high side)
• Signal current > 14.90 A
• Short to battery plus (high
side) signal current < 2.60 A
• Core connection (high side low side) signal current
< 2.60 A

P2177

System Too Lean Off Idle
Bank 1

Adaptive value > 30%

Audi A8/A8L/S8 Quick Reference Specification Book • September 2013 329

DTC Chart

DTC

DTC

Error Message

Malfunction Criteria and
Threshold Value

P2178

System Too Rich Off Idle
Bank 1

Adaptive value < -30%

P2179

System Too Lean Off Idle
Bank 2

Adaptive value > 30%

P217A

Fuel Injector Group “C” Supply Short to ground (high side)
Voltage Circuit/Open
• Signal current > 14.90 A
• Short to battery plus (high
side) signal current < 2.60 A
• Core connection (high side low side) signal current < 2.60
A

P217D

Fuel Injector Group “D” Supply Short to ground (high side)
Voltage Circuit/Open
• Signal current > 14.90 A
• Short to battery plus (high
side) signal current < 2.60 A
• Core connection (high side low side) signal current < 2.60
A

P2180

System Too Rich Off Idle
Bank 2

Adaptive value < -30%

P2181

Cooling System Performance

Cooling system temperature too
low after a sufficient air mass
flow integral < 75° C

P2187

System Too Lean at Idle,
Bank 1

Adaptive value > 6.00%

P2188

System Too Rich at Idle,
Bank 1

Adaptive value < -6.00%

P2189

System Too Lean at Idle,
Bank 2

Adaptive value > 6.00 %

P2190

System Too Rich at Idle,
Bank 2

Adaptive value < -6.00%

P2195

O2 Sensor Signal Stuck Lean
Bank 1 Sensor 1

Delta lambda of 2nd lambda
control loop > 0.070

P2196

O2 Sensor Signal Stuck Rich
Bank 1 Sensor 1

Delta lambda of 2nd lambda
control loop < -0.070

P2197

O2 Sensor Signal Stuck Lean
Bank 2 Sensor 1

Delta lambda of 2nd lambda
control loop > 0.070

P2198

O2 Sensor Signal Stuck Rich
Bank 2 Sensor 1

Delta lambda of 2nd lambda
control loop < -0.070

330 Audi A8/A8L/S8 Quick Reference Specification Book • September 2013

Error Message

Malfunction Criteria and
Threshold Value

P2231

O2 Sensor Signal Circuit
• Delta O2S signal front
Shorted to Heater Circuit Bank
> 0.2 - 0.498 V
1 Sensor 1
• Elapsed time since last O2S
< 0.05 Sec
• Heater switch on

P2234

O2 Sensor Signal Circuit
• Delta O2S signal front
Shorted to Heater Circuit Bank
> 0.2 - 0.498 V
2 Sensor 1
• Elapsed time since last O2S
< 0.05 Sec
• Heater switch on

P2237

O2 Sensor Positive Current
Control Circuit Bank 1 Sensor
1 Open

• O2S signal front 1.46 - 1.54 V
and
• Delta lambda controller
> 0.10

P2240

O2 Sensor Positive Current
Control Circuit Bank 2 Sensor
1 Open

• O2S signal front 1.46 - 1.54 V
and
• Delta lambda controller
> 0.10

P2243

O2 Sensor Reference Voltage
Circuit Bank 1 Sensor 1 Open

• O2S signal front < 0.20 V
and
• Internal resistance > 950Ω

P2247

O2 Sensor Reference Voltage
Circuit Bank 2 Sensor 1 Open

• O2S signal front > 4.70
and
• Internal resistance > 950 Ω

P2251

O2 Sensor Negative Current
Control Circuit/Open Bank 1
Sensor 1

• O2S signal front 1.44 - 1.53 V
and
• Internal resistance > 950 Ω

P2254

O2 Sensor Negative Current
Control Circuit/Open Bank 2
Sensor 1

• O2S signal front 1.44 - 1.53 V
and
• Internal resistance > 950 Ω

P2257

Secondary air injektion
System Control "A" Circuit
Low

Signal voltage 0.00 - 3.26 V

P2258

Secondary air injektion
System Control "A" Circuit
High

Signal current 0.60 - 2.40 A

P2259

Secondary Air Injection
System Control "B" Circuit
Low

Signal voltage 0.0 - 3.26 V

P2260

Secondary Air Injection
System Control "B" Circuit
High

Signal current 0.60 - 2.40 A

Audi A8/A8L/S8 Quick Reference Specification Book • September 2013 331

DTC Chart

DTC

DTC

Error Message

Malfunction Criteria and
Threshold Value

P2270

O2 Sensor Signal Stuck Lean;
Bank 1 Sensor 2

• O2S signal rear not oscillating
at reference < 0.64 V
and
• Enrichment after stuck lean
28%

P2271

O2 Sensor Signal Stuck Rich;
Bank 1 Sensor 2

• O2S signal rear not oscillating
at reference > 0.64 V
and
• Enrichment after stuck rich
15%
or
• Sensor voltage (after fuel cut
off) ≥ 0.15V
and
• Number of checks ≥ 1.0

P2272

O2 Sensor Signal Stuck Lean;
Bank 2 Sensor 2

• O2S signal rear not oscillating
at reference < 0.64 V
and
• Enrichment after stuck lean
28%