P0138

272A - P0138

Information saved in
DME

Fault code
272A - P0138

Fault text
Oxygen sensor, electrical diagnosis, behind cat., Bank 1

Fault description


Condition for fault identification
Test condition:
* Sensor heater must be active since at least
K_LSHNK_AKTIV_T *Exhaust gas temperature >
K_LANK_DIAG_TKat *LA controller is active since
K_LANK_DIAG_VK_REG_T *Sensor temperature >
K_LANK_DIAG_SONDTEMP *Cat temperature >
K_LANK_TKat_SCHW
Terminal condition: Engine running
Voltage condition:
ub > K_ED_PlusMin

Condition for fault memory entry
Oxygen sensor voltage
lank_us_b1 > K_LANK_DIAG_UMax
for min. K_LANK_DIAG_Max_T

Action in service
1. Check plug and wiring harness to post-catalyst oxygen
sensor behind Bank 1 catalyst
2. If OK, replace oxygen sensor

Fault effect and breakdown warning
MIL lamp lights up after engine runs 2X

Driver information
Warning light:
No

Service instruction
none