P0436 Catalyst Temperature Sensor Circuit Range/Performance Bank 2 Sensor 1

Some engines – mainly diesels – measure the temperature at or in the catalyst with a thermistor in a voltage divider instead of only modelling it; most makers report exhaust temperature sensors under P0544 ff, P2031 ff or P2080 ff instead. Sensor 1 of bank 2 is the first catalyst temperature sensor on the side without cylinder 1. P0436 means the signal is electrically valid but implausible – compared with the temperature model or neighbouring exhaust sensors it is off, sluggish or frozen. No manufacturer document available to us uses this code; the description follows CARB, which requires input circuits to be checked for circuit faults and plausibility, and the comparable exhaust temperature sensors.

Likely causes

Symptoms

• Check engine light on
• Usually no noticeable change (substitute value from the model)
• Diesel: filter regeneration distorted or blocked, possibly further codes such as P2459 or P0420

Repair estimate

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

Related codes

References: law.cornell.edu, hella.com, gsi.ext.gm.com.