Testing For Electrical INTERMITTENTS

Perform the following procedures while wiggling the harness from side to side. Continue this at convenient points (about 6 inches apart) while watching the test equipment.

• Test for short to ground.
• Test for continuity.
• Test for a short to voltage.

If the fault is not identified, perform the procedure below using the MIN MAX feature on DMM (J 39200). This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will generate an audible tone when a change is detected.

1. Connect DMM (J 39200) to both sides of a suspected connector (still connected), or from one end of a suspected circuit to the other.
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position.
3. Press the range button of the DMM in order to select the desired voltage range.
4. Press the MIN MAX button of the DMM. The DMM displays 100 ms RECORD and emits an audible tone (beep).
NOTE: The 100 ms RECORD mode is the length of time an input must stay at a new value in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling the connections or the wiring, test driving, or performing other operations. See INDUCING INTERMITTENT FAULT CONDITIONS .
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has been recorded.
7. Press the MIN MAX button once in order to display the MAX value, and note the value.
8. Press the MIN MAX button again in order to display the MIN value, and note the value.
9. Determine the difference between the MIN and MAX values.
   • If the variation between the recorded MIN and MAX voltage values is one volt or greater, an intermittent open or high resistance condition exists. Repair the condition as necessary.
   • If the variation between the recorded MIN and MAX voltage values is less than one volt, an intermittent open or high resistance condition does not exist.