TEST 2: Verifying The 12 Volt Start Signal
One of the things that can lead you to believe that the starter motor is bad is a dead battery. So, it's important that the battery on your Honda Civic is in a fully charged condition.
How can you find out? Well, one very fast test you can do to find out is to: Turn the key to the on position and then turn on the headlights for about 10 seconds (and after 10 seconds turn them off). Then, check the voltage, with your multimeter in Volts DC, of the battery. If the battery's voltage is around 12.4 Volts, then the battery is OK.
One other thing, both the positive and negative battery terminals and posts must be clean before you start this first test.
OK, enough yakking, here's what you'll need to do:
- 1
Set your multimeter to Volts DC mode.
- 2
With the red multimeter test lead, probe the wire that connects to the S terminal of your Honda Civic's starter motor solenoid.
How? by piercing the wire with a tool like a wire piercing probe (or any other suitable tool that you can attach the red multimeter test lead to). - 3
Ground the black multimeter test lead on the battery negative (-) post.
- 4
When you've gotten everything set up, have an assistant crank the engine.
The engine won't crank, but this is the only way to test and confirm the presence of the Start signal from the ignition switch (and by extension, verifying that the neutral safety switch is working too). - 5
Your multimeter will register one of two things:
1.) You'll see 10 to 12 Volts DC (if the ignition switch and the neutral safety switch are good).
2.) Your multimeter will register 0 Volts (which usually indicates that the ignition switch or the neutral safety switch is fried).
OK, let's make sense of the readings that your multimeter recorded in the test:
CASE 1: Your multimeter registered 10 to 12 Volts. This let's you know that both the ignition switch and the neutral safety switch are doing their job and supplying the Crank (Start) Signal.
Now, around 90% of the time, you could stop here and condemn the starter motor as bad and replace it and the problem would be solved. But to be absolutely sure, I suggest doing one more test.
The next test would be to voltage drop test the battery positive wire that connects to the starter motor with the nut. This is an easy and fast test, go to: TEST 3: Voltage Drop Testing The Batt (+) Cable.
CASE 2: If your multimeter DID NOT register 10 to 12 Volts. This tells you that the either the ignition switch or the neutral safety switch is bad. Without this Start (Crank) signal, the starter motor will not come alive and crank the engine.
Now, it's beyond the scope of this article to test either the ignition switch or the neutral safety switch, but you have at least eliminated the starter motor itself as bad.
TEST 3: Voltage Drop Testing The Batt (+) Cable
One common issue I've seen that can prevent your 1.6L Honda Civic from cranking and starting is hidden corrosion on the battery positive (+) terminal.
As you may already know, this cable supplies the starter motor with the power it needs to crank the engine.
If the cable can't deliver the full power from the battery, the starter motor won't be able to do its job and crank the engine.
This is where the voltage drop test comes in handy. It provides a clear result: either a 'YES, this circuit is OK' or a 'NO, this circuit has a problem.'
Alright, here's what you need to do:
- 1
Place your multimeter in Volts DC mode.
- 2
Probe the Batt + stud on the starter motor with the red multimeter test lead.
NOTE: This stud is the one that has the big cable attached to it with a nut (see the photo above). Do not probe the cable's round terminal, probe the stud itself. - 3
Connect the black multimeter test lead to the center of the battery positive (+) post.
- 4
When you're ready, have your helper crank the engine while you observe the multimeter.
Although the starter motor won't crank the engine, a voltage drop test of this cable (circuit) requires that you turn the key and crank the engine. - 5
You'll get one of two results on your multimeter:
1.) The multimeter will register a 0 voltage which indicates no voltage drop.
2.) The multimeter will register a voltage, usually 5 Volts or more and this test results means that there is a voltage drop in the circuit and this is not good.
OK, now that the testing part is done, let's take a look at what your results mean:
CASE 1: Your multimeter indicated NO voltage drop (which is 0.5 Volts or less). This confirms that the battery positive cable is corrosion free and supplying all of the available battery power to the starter motor.
With this test result you can replace the starter motor with confidence. Now, in case you're reading this article because you've already replaced the starter motor and that did not solve your ‘no-crank’ condition, I recommend doing the following tests:
1.) Turn the engine manually (using a 1/2 ratchet and the appropriate socket). This will verify that the engine is not mechanically locked up. After all, it could've thrown a rod and this is what is keeping the engine from cranking. Or the A/C compressor could be locked up too (I have seen this a lot!) and this will also make you think it's a bad starter motor.
2.) Bench test the starter motor. You could have received a defective starter motor right out of the box! Bench Testing a starter motor is easy and you can find the step-by-step instructions here: How To Bench Test A Starter Motor (Step By Step) (at: easyautodiagnostics.com).
CASE 2: Your multimeter registered 5 Volts or more. This result confirms that a voltage drop indeed exists in this circuit. In non-technical terms, this means that corrosion is keeping the cable from delivering all of the battery's available power. This corrosion almost always shows up on the terminal ends of the cable.
To solve this issue all you have to do is clean both ends of the battery positive cable. By both ends, I mean the end that connects to the battery positive post and the end that attaches to the starter motor solenoid. In case you're wondering how to clean the end that attaches to the starter motor solenoid, you can use sand paper to sand both sides of the round terminal.
Once you're done and have reconnected both ends of the cable, re-test or simply crank up the car. More than likely it'll now crank and start.
More 1.6L Honda Civic Tutorials
You can a complete list of 1.6L Honda Civic diagnostic tutorial in this index:
Here's a small sample of the tutorials you'll find in the index:
- How To Test Engine Compression (1995-2000 1.6L Honda Civic).
- How To Test The Throttle Position Sensor (1995-2000 Honda 1.6L).
- How To Test For A Blown Head Gasket (1995-2000 1.6L Honda Civic).
- How To Troubleshoot A No Start (1995-2000 1.6L Honda Civic).
If this info saved the day, buy me a beer!
