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Testing The Relay
Since your Ford vehicle uses quite a few of the exact same type of relay, you can swap them out and in this way test them. But if you're like me, sometimes you need a real test to make absolute sure that the relay is bad.
Well, you've come to the right place for such a test.
You'll need three very important things:
- A multimeter (analog or digital).
- Two jumper wires with alligator clips on the ends.
- Maybe a helper.
OK, to get this test going, this is what you'll need to do:
- Place the relay you need to test close to the vehicle's battery (you'll need battery power and Ground for this test).
- Using a jumper wire with alligator clips, connect terminal 85 of the relay to the battery's Ground (-) terminal
- The photos in the image viewer are an exact representation of what goes where.
- If you don't have such a jumper wire (with alligator clips), you can run down to your local Radio Shack (even Wal-Mart) and buy some and make your own jumper wire.
- Activate the relay by connecting male spade terminal 86 to the battery's positive (+) terminal.
- It's normal to hear a small clicking from the relay when this connection is made.
- With your multimeter in Ohms mode: touch terminals 30 and 87 with the multimeter leads (as seen in the photo).
- It doesn't matter which color lead goes where, since the polarity does not matter for this test.
- You may need a helper for this operation, unless your multimeter leads have alligator clips on the end of the leads.
- Once the last connection is made, your multimeter should show continuity. If it doesn't show continuity, recheck all your connections and retest.
- Remove and reconnect the jumper wire to terminal 86 several times, as you eye-ball the multimeter.
- When the jumper wire IS NOT connected to power, the multimeter should show NO CONTINUITY.
- When the jumper wire is connected to power, the multimeter should show continuity.
OK, let's interpret your test results:
CASE 1: Your multimeter showed continuity. This tells you that the relay is OK and not the cause of the problem.
CASE 2: Your multimeter DID NOT show continuity. This tells you that the relay is bad and needs to be replaced.
If this info saved the day, buy me a beer!