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Recirculation/Fresh Control Circuit

  1. Remove control panel. See CONTROL PANEL  under REMOVAL & INSTALLATION. Connect battery positive lead to terminal "D" of 7-pin connector and negative lead to terminal "L" of 21-pin connector of electronic control panel. See Fig 1 . Leave battery connected to these terminals during testing procedures.
  2. Connect jumper wire between terminals "L" and "M" of 21-pin connector. Connect a resistance of at least 1000 ohms between terminals "B" and "O" of 21-pin connector. Measure voltage between terminals "B" and "O" of 21-pin connector. If voltage is approximately 12 volts, go to next step. If voltage is NOT approximately 12 volts, replace electronic control panel.
  3. Disconnect resistance and jumper wire connected in step 2). Connect a resistance of at least 1000 ohms between terminal "D" of 7-pin connector and terminal "B" of 21-pin connector. Measure voltage between terminals "B" and "O" of 21-pin connector. If less than one volt is present, go to next step. If more than one volt is present, replace electronic control panel.
  4. Disconnect resistance connected in step 3). Place RECIRCULATION/FRESH button in FRESH position (button out). Using an ohmmeter, check continuity between terminals "L" and "N" of 21-pin connector. See Fig 1 . If there is continuity, go to next step. If there is no continuity, replace electronic control panel.
  5. Place RECIRCULATION/FRESH button in RECIRCULATION position (button in). Using an ohmmeter, check continuity between terminals "L" and "P" of 21-pin connector. If there is continuity, RECIRCULATION/FRESH control circuit of electronic control panel is okay. If there is no continuity, replace electronic control panel.
Fig 1: Identifying Electronic Control Panel Connector Terminals
G91H04855Courtesy of MAZDA MOTORS CORP.