Testing For An Open Circuit Using An Ohmmeter

Courtesy of CHRYSLER GROUP, LLC

NOTE:

Before measuring the resistance of any circuit, first measure the resistance between the two leads of the multimeter. Take this value and subtract it from the value recorded when measuring the resistance of the circuit being checked (The meter leads can add 0.5 ohm or more of total resistance).

Turn the ignition off.
Disconnect the wire harness connectors of the components that contain the circuit suspected of being open.
NOTE:
Check connectors - Clean/repair as necessary.
At this time leave all in-line connectors connected.
With the component wire harness connectors disconnected, use a multimeter set to Ohms (?), and measure the resistance of the circuit.
Use one lead of the meter and probe the circuit in one harness connector.
Use the other lead of the meter and probe the same circuit in the other harness connector.
Is the resistance in the circuit below 3.0 ohms?

Yes
- The circuit does not contain any excessive resistance or the condition that originally caused the excessive resistance may not be present at this time. Continue to measure the resistance of the circuit, wiggle the wire harness and connectors to check for an intermittent open or poor connection.
- Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors where the open could occur intermittently.
- Look for any chafed, pierced, pinched, or partially broken wires.
- Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related wire harness connectors.
- Perform any Technical Service Bulletins (TSBs) that may apply.
No
- Repair the excessive resistance in the circuit between the two wire harness connectors. Using the wiring diagram as a guide, trace the circuit and check for any in-line connectors where the open or excessive resistance could occur.
- One method to help isolate the open is to disconnect any in-line connectors and measure the resistance from one side of the in-line connector to the matching component harness connector. If the open or excessive resistance is not present, the open or excessive resistance is on the other side of the in-line connector.