Open Circuit Check

Possible causes for the open circuit are as listed below. As defects in connectors or terminals are most often the causes, they need to be checked particularly carefully.

• Loose connection of connector
• Poor contact of terminal (due to dirt, corrosion or rust on it, poor contact tension, entry of foreign object, etc.)
• Open wire harness

When checking circuits including an electronic control unit such as ECM, TCM, ESP® control module, etc., it is important to carefully perform check, starting with items which are easiest to check.

1. Disconnect negative (-) cable at battery
2. Check connectors at both ends of the circuit being checked for loose connection. Also check lock condition of connectors if equipped with connector locks.
   Fig 1: Checking Connectors For Looseness

   Courtesy of SUZUKI OF AMERICA CORP.
3. Using a male terminal for test use, check terminals on both ends of the circuit being checked for contact tension of female terminals. Check each terminal visually for cause of poor contact (dirt, corrosion, rust, entry of foreign object, etc.). At the same time, check that each terminal is held and locked in connector fully.
   Fig 2: Checking Contact Tension

   Courtesy of SUZUKI OF AMERICA CORP.
4. Perform CONTINUITY TEST  or VOLTAGE CHECK  using the following procedures, to check the wire harness for open circuit and poor connection at its terminals.
   Fig 3: Identifying Wire Harness For Open Circuit And Poor Connection

   Courtesy of SUZUKI OF AMERICA CORP.