U0687

Lost Communication With Catalyst Temperature Bank 2 Sensor 2

Severity

⚠️ Medium

Can you drive?

Yes, but get it checked soon

Approx. repair cost

$28–89 (est.)

Symptoms

Check Engine light comes on
Possible increase in fuel consumption
Decrease in catalyst efficiency
The car may go into emergency mode
Errors in the operation of the exhaust system

Causes

Open or short circuit in the sensor circuit
Malfunction of the catalyst temperature sensor itself
Connector problems or contact corrosion
Engine control module malfunction
Wiring harness damage

How to Fix

Check the integrity of the wiring to the temperature sensor
Inspect the sensor connectors for corrosion or damage.
Check the resistance of the temperature sensor (compare with specifications)
If necessary, replace the catalyst temperature sensor
Check and, if necessary, reflash the ECU

Related codes

U0688 U0690 P0420