2B59

2B59 - P0128

Information

saved in
DME

Fault code
2B59 - P0128

Fault text
Coolant thermostat monitoring

Fault

description


Condition

for fault

identification
Test condition:
Engine starting temperature with coolant temperature below 60 deg C
Terminal condition: Engine running
Voltage condition:
none

Condition

for fault

memory

entry
1. For a period of K_TMOT_OBD_DIFF_T_DELTA the sensor error is
more than K_TMOT_OBD_DIFF_Max relative to the model and the
temperature at the radiator outlet has increased by more than
K_TMOT_OBD_K�hleraustrittstemperatursensor_THERM_1_DELTA.
2. Sensor movement has been less than KL_TMOT_OBD_DELTA

Action in

service
1. Replace thermostat
2. Perform electrical check on coolant sensor and replace as indicated

Fault effect

and

breakdown

warning
Engine warms to normal operating temperature very slowly / ineffective
interior heating / MIL on after engine runs 2x

Driver

information
Warning light:
No

Service

instruction
none