Checking the front heater relay
1. Check for continuous continuity between terminals 1 and 3.
2. Check for continuous continuity between terminals 2 and 4 of the relay.
3. Check for continuity only between terminals 4 and 5 of the relay when there is battery voltage at terminals 1 and 3.
4. If the conductivity between the relay terminals does not correspond to the specified value, replace the relay.
Checking the rear heater relay
1. Check for continuous continuity between terminals 1 and 3 of the relay.
2. Check for continuity only between terminals 2 and 4 of the relay with battery voltage at terminals 1 and 3.
3. If the conductivity between the relay terminals does not correspond to the specified value, replace the relay.