Defogger Relay Test: MPV

Remove defogger relay. Check continuity between defogger relay terminals "B" and "D". See Fig 1 . If continuity exists, replace defogger relay. If continuity does not exist, apply battery voltage across defogger relay terminals "A" and "C". Check continuity between defogger relay terminals "B" and "D". If continuity exists, defogger relay is okay. If continuity does not exist, replace defogger relay.

Fig 1: Identifying Defogger Relay & Internal Circuit (MPV)

Courtesy of MAZDA MOTORS CORP.