Oxygen Sensor Relay: Testing and Inspection

Oxygen Sensor Heater Relay:

- Remove heater relay from its bracket and disconnect coupler from it.

Inspecting Relay (Resistance):

O2 Sensor Relay Specification:

- Check resistance between each two terminals as shown in illustration.
- If check results are as specified, proceed to next operation check. If not, replace.

Inspecting Relay (Function):

- Check that there is continuity between terminals "A" and "B" when battery is connected to terminals "C" and "B". If found defective, replace.
- Connect coupler to relay securely and install it to it's bracket.