Delco 27SI Troubleshooting – Charging System

Test Step 10. TEST FOR UNDESIRABLE CURRENT FLOW IN THE ALTERNATOR CHARGING SYSTEM.

1. Turn off all of the accessories. Turn the keyswitch to the OFF position.

2. Clamp a 9U-5795 Current Probe or 225-8266 Ammeter Tool Gp around the main ground cable. Clamp the tool with the positive side away from the battery. Reset the probe (zero) before you clamp the probe around the wire. Read the current on the meter. Make a note of the current that was measured.

Expected Result:

The current is below 2 A. The “YES” selection is dependent on the presence of a main disconnect switch on the machine that is being tested.

Results:

• YES – WITH DISCONNECT SWITCH – The current is below 2 A. For machines with a main disconnect switch, proceed to test step 11. 
• YES – WITHOUT DISCONNECT SWITCH – The current is below 2 A. For machines without a main disconnect switch, proceed to test step 12. 
• NO – The current is above 2 A. There is a current draw in the system. Proceed to test step 13.