B Terminal Circuit

B TERMINAL CIRCUIT

Description

"B" terminal circuit supplies power to charge the battery and to operate the vehicles electrical system.


Diagnosis Procedure


1. CHECK "B" TERMINAL CONNECTION

1.Turn ignition switch OFF.
2.Check if "B" terminal is clean and tight.
Is the inspection result normal?
YES- GO TO 2.
NO- Repair "B" terminal connection. Confirm repair by performing complete Charging system test using EXP-800 NI or GR8-1200 NI (if available). Refer to the applicable Instruction Manual for proper testing procedures.

2. CHECK "B" TERMINAL CIRCUIT

Check voltage between alternator "B" terminal and ground.





Is the inspection result normal?
YES- GO TO 3.
NO- Check harness for open between alternator and fusible link.

3. CHECK "B" TERMINAL CONNECTION (VOLTAGE DROP TEST)

1.Start engine, then engine running at idle and warm.
2.Check voltage between battery positive terminal and alternator "B" terminal.





Is the inspection result normal?
YES- "B" terminal circuit is normal. Refer to "Work Flow (With EXP-800 NI or GR8-1200 NI)" With EXP-800 NI or GR8-1200 NI or "Work Flow (Without EXP-800 NI or GR8-1200 NI)" Without EXP-800 NI or GR8-1200 NI.
NO- Check harness between battery and alternator for poor continuity.