In this tutorial I'm gonna' show you how to test the starter motor in a step-by-step manner. No expensive diagnostic tools needed!
All of the tests are explained in plain English so that you can easily find out if the starter motor is bad or not.
NOTE: You'll notice that the photos I'm using are of the starter motor off of the vehicle; this is to make it easier to show you where to make your test connections. You don't need to remove the starter motor from your Ford to follow the test instructions in this tutorial.
Contents of this tutorial:
- Important Tips.
- Symptoms Of A Bad Starter Motor.
- Tools Needed To Test The Starter Motor.
- TEST 1: Applying 12 Volts To The S Terminal.
- TEST 2: Verifying The 12 Volt Start Signal.
- TEST 3: Testing The Starter Motor Relay's Activation Signal.
- TEST 4: Voltage Drop Testing The BAT (+) Cable.
- More Ford E150, E250, and E350 Tutorials.
APPLIES TO: This tutorial applies to the following vehicles with a 4.9L, 5.0L, or 5.8L engine:
- Ford E150: 1992, 1993, 1994, 1995, 1996.
- Ford E250: 1992, 1993, 1994, 1995, 1996.
- Ford E350: 1992, 1993, 1994, 1995, 1996.
The following wiring diagrams may come in handy:
- Starter Motor Circuit Diagram (1992-1993 Ford E150, E250, E350).
- Starter Motor Circuit Diagram (1994-1995 Ford E150, E250, E350).
TIP 1: Before you start testing the starter motor, make sure that the battery is fully charged. This is super critical, or you may end up getting the wrong test result.
TIP 2: The battery cable terminals and the battery posts should be clean and corrosion-free before starting the tests.
TIP 3: Read the entire article first so that you can familiarize yourself with the tests.
TIP 4: Use jack stands for safety.
You'll need to raise your Ford E-Series van to access the starter motor. Do not trust the jack alone to keep your vehicle up in the air while you're underneath it!
TIP 5: Take all necessary safety precautions, like use safety glasses while working underneath the vehicle. Be alert and think safety all of the time.
Symptoms Of A Bad Starter Motor
For the most part, when the starter motor fails, the engine will not turn over when you turn the key to crank and start the engine.
In some cases, the starter motor fails intermittently, which means that it'll work fine most of the time, but it won't now and then.
Here's a list of the most common symptoms will see where the starter motor has failed:
- You turn the key to crank up and start the engine but nothing happens.
- You got someone to help your jump-start your Ford, but this didn't help get the engine to crank and start.
- You've bought a brand new battery (thinking that was the solution to the 'no-crank' condition) and this did not get your Ford to crank and start.
- Turn the key to start your Ford and all you hear is a small knock and nothing else.
Although the above list is not a complete list of symptoms, the theme that runs thru them and any other related symptom is that the engine will not turn over when you turn the key to start it.
Tools Needed To Test The Starter Motor
You don't need expensive test equipment to test the starter motor on your E-Series van, but you do need a few things. These are:
- You'll need to raise your vehicle to gain access to the starter motor.
- Jack stands.
- Remote starter switch.
- If you'd like to see what a remote starter switch looks like, you can follow this link: Actron CP7853 Remote Starter Switch For 6V And 12V Automotive Starting Systems
- You can either buy this tool online or you can buy it at your local auto parts store (AutoZone, O'Reilly, Pepboys, etc.).
- Multimeter or a 12 Volt automotive test light.
- If you don't have a multimeter or need to upgrade yours, check out my recommendation here: Buying A Digital Multimeter For Automotive Diagnostic Testing (at: easyautodiagnostics.com).
- A wire piercing probe.
- This tool is not an ‘absolute must-have tool’ but I can tell you from experience that it makes it a whole lot easier to probe the S terminal wire for the Start Signal.
- If you'd like to see what this tool looks like, you find out more about it here: Wire Piercing Probe Tool Review (Power Probe PWPPPPP01).
- A helper.
As you can see, you don't need anything expensive. OK, let's turn the page and get started with the first starter motor test.