Starting System Fault Ford F150: 9 Reasons And Fixes!

There are several possible reasons for a starting system fault in a Ford F150, including a bad/dead battery, blown fuse, wiring damage, faulty ignition, faulty starter motor, malfunctioning alternator, misleading security code, and a weak camshaft position sensor. To diagnose and solve the issue, you need to inspect and test each component using the appropriate tools and techniques.

This is not the whole scenario behind the Ford F-150 system problem. For the whole explanation go through till the end. 

9 Reasons Behind Ford F150 Starting System Fault 

There are multiple reasons behind the Ford F150 starting system fault. Starting system fault is typically an error notification that arises on the dashboard for problems related to the engine starting.  The following table contains all the potential causes of this issue.

Bad/dead batteryCheck the battery with a multimeterReplace or recharge the battery
Blown fuseVisually inspect the fuseReplace the fuse
Wiring damageInspect the wiringRepair the wiring
Faulty ignition/ key fobVisually inspect the ignition switchRepair or replace the ignition switch
Faulty starter motorCheck the starter motor terminals for voltageReplace the starter motor
Malfunctioning alternatorCheck charging system voltage and amperageReplace the alternator
Misleading security codeVerify the security coden/a
The weak camshaft position sensorCheck the sensor’s output with a diagnostic toolReplace the camshaft position sensor
Faulty fuel systemInspect the fuel systemFix the faulty component of the fuel system

Now, let’s discuss issues briefly along with the diagnosis and solution. 

Reason 1: Bad/Dead Battery

A bad or dead battery can cause starting system faults in a Ford F150. The battery provides the initial power to the starter motor, which then engages the engine’s flywheel to start the engine. If the battery is dead or not providing enough power, the starter may not be able to turn the engine over, which can trigger a starting system fault.

Diagnosis: Check The Battery With A Multimeter

Use a voltmeter to check the battery’s voltage. Battery voltage should be around 12.6 volts when fully charged. Battery charging may be necessary if the voltage is lower than this. 

On the other hand, If the battery frequently drains away rapidly or constantly causes the slow engine crank it indicates that the battery needs to be replaced. 

Solution: Replace or Recharge Your Ford F150 Battery

Battery replacement is necessary if the battery is completely dead. We recommend consulting a professional automobile mechanic in this situation.

Reason 2: Blown Fuse

A blown fuse in the starting system of a Ford F150 can cause a starting system fault in several ways. The starting system of a vehicle typically consists of several components, including the battery, starter motor, ignition switch, and various electrical connections.

When a fuse blows in the starting system, it may prevent power from reaching one or more of these components, preventing the vehicle from starting. In the case of a blown starter motor fuse, the motor will not receive electricity to turn over the engine.

Diagnosis: Visually Inspect The Fuse

To visually inspect a blown fuse, follow these steps:

  1. Disconnect the battery to Shut down the circuit that you are inspecting.
  2. In the fuse box or panel, locate the fuse. The steering fuse in the Ford F150 is located in the passenger compartment fuse box, which is located under the glove box on the right side by the kick panel. Fuse number is 13 for ford F150 2015 to 2019
  3. Look at the fuse to see if the metal strip inside is intact or broken.
  4. If the metal strip is intact, the fuse is not blown. It is a blown fuse if the metal strip is broken.

Solution: Replace the Fuse 

In the event of a fuse becoming damaged, the sole course of action is to replace it. However, before replacement, it is imperative to ascertain the amperage rating of the blown fuse and procure a replacement fuse of an identical rating.

Reason 3: Wiring Damage

Wiring damage can cause a Ford F150 starting system fault through corroded/frayed wires, loose/disconnected wires, short circuits, and damaged connectors/terminals. These issues can result in difficulty starting the engine or a malfunctioning starting system.

Diagnosis: Inspect The Wiring

Visually inspect the wiring in the starting system to check for signs of damage, such as frayed or corroded wires, loose or disconnected wires, or damaged connectors or terminals. These signs indicate potential wiring damage. Find out the wires under the plastic cover behind the steering wheel.

Solution: Repair the Wiring Damage

Repairing the wiring damage is a critical process to perform. So, you should better consult a professional automobile mechanic to do this correctly.  

Reason 4: Faulty Ignition

A faulty ignition system can cause starting system faults in a Ford F150 because the ignition system is responsible for providing the necessary spark to ignite the fuel in the engine. Engines that are not starting properly or that are running poorly can be caused by a malfunctioning ignition system.

Diagnosis: Inspect The Ignition Switch

Diagnosing a faulty ignition system in a Ford F150 can be challenging and requires some mechanical knowledge and experience. To diagnose and resolve this issue you should better contact an automobile mechanic. 

Reason 5: Faulty Starter Motor

A faulty starter motor in a Ford F150 can cause a starting system fault by preventing the engine from starting or cranking properly. In the event that the starter motor malfunctions, the engine may not run at all or may run very slowly, as it is responsible for turning the engine over.

Car Starter Motor

Diagnosis: Check For Voltage At The Starter Motor Terminals

To check for voltage at the starter motor terminals, follow these steps:

Step 1: Turn off the ignition and remove the key from the ignition switch to prevent any accidental starting of the engine.

Step 2: Locate the starter motor under the vehicle, typically on the passenger side of the engine bay.

Step 3: Locate the two terminals on the Ford F-50 starter motor. One will be the large positive terminal where the battery cable connects, and the other will be a smaller terminal where the starter solenoid wires connect. It’s typically located on the passenger side of the engine block, towards the transmission bell housing.

Step 4: Check the voltage at the smaller starter motor terminal with a digital multimeter. Set the multimeter to DC voltage and touch the positive lead to the smaller starter motor terminal and the negative lead to a ground point on the vehicle.

Step 4: Take assistance from another person to turn the ignition key to the start position while you monitor the multimeter reading. If you see voltage at the small starter motor terminal (typically between 10.5 and 12 volts), then the problem may be with the starter motor itself. 

If there is no voltage or a low voltage reading, the problem may be with the ignition switch, starter relay, or wiring.

Solution: Replace the Starter Motor

Replacing the starter motor in a Ford F150 can be a challenging task, but it is possible to do it yourself with the right tools and some patience. To make it easy for you, here’s a step-by-step guide:

Tools Needed:

  1. Socket wrench set
  2. 6-inch extensions
  3. 3/8 or larger ratchet
  4. Rags
  5. Wire brush

Step 1: Remove the negative battery cable with a socket wrench. Wrap it in a rag and tuck it away from the starter. Cover the ground with a rag as well.

Step 2: Remove the main power wire and S terminal of the starter motor using a 13-millimeter socket wrench. The S-terminal will be a 10-millimeter. The main power wire in the Ford F150 is typically red in color and S terminal is black. 

Step 3: Remove the ground stud using a 13-millimeter nut and a 15-millimeter socket wrench. It’s recommended to use a 3/8 or larger ratchet since the nut is usually tight or rusted. Ground studs in Ford F-150 are located on the left and right side bulkhead, on both the inside and outside of the vehicle

Step 4: Remove the lower bolt on the starter motor. Loosen it but leave it in place to keep the starter from falling. Remove the second bolt all the way out.

Step 5: Remove the third bolt, which is located at the top of the starter motor. This can be tricky, but using a 6-inch extension and a standard-length socket on the other end can help. You may need to use a 3/8 drive if it’s too tight.

Step 6: Once you remove the third bolt, carefully remove the starter motor from the vehicle. Be careful not to hit it against the wheel pan since it could arc right through it.

Step 7: Clean the mounting surface of the starter motor using a wire brush.

Step 8: Replace the starter motor in the reverse order in which you removed it. Start by inserting the top bolt first, followed by the second bolt, and finally the lower bolt. Tighten them using a socket wrench.

Step 9: Reconnect the power wire and ground stud using the appropriate socket wrench sizes.

Step 10: Using a socket wrench, reconnect the negative battery cable.

Step 11: Finally, Turn on the ignition and check if the starter motor is working properly.

There you have it! These steps should guide you through replacing the starter motor on your Ford F150. Remember to take your time and be careful not to damage anything in the process.

Reason 6: Malfunctioning Alternator

A malfunctioning alternator in a Ford F150 can cause starting system faults by draining the battery, not providing enough power to the starter, or causing other electrical system components to malfunction. 

The alternator normally charges the battery while the engine is running, but if it’s not functioning correctly, the battery may not have enough power to turn the engine over. The starter motor requires significant power to turn the engine, and if the alternator can’t provide it, the starter won’t work.

Diagnosis: Check Charging System Voltage And Amperage

To diagnose an alternator problem, you can use a voltmeter to test the alternator’s output. Check the battery to ensure it has enough voltage to start the vehicle. Then, start the engine and rev it to 2000 RPM while testing the battery’s voltage with the voltmeter. 

Depending on the RPMs and accessories, the voltage should rise to at least 13 volts and remain between 13 and 14.5 volts. You can also monitor the alternator gauge, listen for any unusual noises, or take the alternator to an auto-parts store for free testing.

Solution: Replace The Alternator

Replacing the alternator is a challenging task. It requires a higher level of expertise in automobile technology. However, if you are a DIY person you can refer to the video below for the guide to replacing your Ford F-150 alternator.  

Reason 7: Misleading Security Code

Misleading security codes can trigger the anti-theft mode on the Ford F150, causing a starting system fault. When the anti-theft mode is enabled, the ‘THEFT’ light will flash continuously, indicating that the system thinks the truck has been stolen. As a result, the system will disable the ignition and prevent the vehicle from starting.

The security code is used to authenticate the key or remote users to start the vehicle. If the security code does not match the code stored in the vehicle’s computer, it will trigger the anti-theft mode and prevent the vehicle from starting.

Diagnosis: Verify The Security Code

If you suspect that the security code on your Ford F150 is misleading, you should check the fuses and relays first. Faulty fuses and relays can sometimes send false theft signals to the vehicle’s computer system. 

If the fuses and relays check out, the system will automatically email you a theft code. You can then email this code to the manufacturer for verification and resolution of the problem.

Reason 8: The Weak Camshaft Position Sensor

A weak or faulty camshaft position sensor in a Ford F150 can cause a starting system fault. This means that the engine may have difficulty starting or may not start at all. 

The sensor is responsible for providing the engine control module with accurate information about the position of the camshaft, which is used to synchronize the fuel injection and ignition timing. If the sensor is weak or faulty, it may not be able to provide this information, resulting in incorrect timing and difficulty starting the engine.

Diagnosis: Check The Sensor’s Output With A Diagnostic Tool

If you have an OBD (On-Board Diagnostics) system in your vehicle, you can diagnose a weak camshaft positioning sensor by reading the error codes stored in the system. If the sensor is weak, the system will likely generate an error code, such as P0340, indicating a malfunction with the camshaft position sensor circuit.

P0340 is a common error code for camshaft position sensor issues. When this error code appears, it means that the OBD system has detected a problem with the sensor’s signal or circuit.

You can also refer to the video below for the guide on how to check the camshaft position sensor. HOW TO TEST CAMSHAFT POSITION SENSOR ON A CAR

Solution: Replace The Camshaft Position Sensor

To replace the camshaft position sensor, you’ll need the following tools:

Ratchet and socket set

  1. Torque wrench
  2. Rag or towel
  3. Compressed air (optional)

Here are the step-by-step instructions:

Step 1: Locate the camshaft position sensor. Most engines have it mounted on the cylinder head, near the top.

Step 2: Remove the connector from the sensor. There is a tab on the back that you’ll need to push down and slide off.

Step 3: Clean the area around the sensor with a rag or compressed air to ensure that no dirt or debris enters the engine.

Step 4: Take out the eight-millimeter bolt that holds the sensor in place. Next, gently wiggle the sensor to remove it from the socket.

Step 5: Check to ensure that the o-ring on the old sensor came out with the sensor. Check that there is an o-ring on the new sensor.

Step 6: Insert the new sensor into the hole where the old one was. Ensure that the o-ring is fully seated.

Step 7: Install the eight-millimeter bolt and torque it down to 89-inch pounds or 7.4 foot pounds. Afterward, reconnect the sensor plug.

Step 8: Reinstall the air intake plumbing and tighten the 10-millimeter bolt to 80-inch pounds or 6.67-foot pounds. Reconnect the negative terminal on your battery. Finally, set the sensor by starting the engine and checking for proper operation.

That’s it, you have successfully replaced your camshaft position sensor! For visual guidance, you can also refer to the video below.

However, if you feel these steps are hard to perform you can consult a professional automobile mechanic to do it. The average cost for camshaft position sensor replacement is between $100 and $250, including parts and labor.

Reason 9: Faulty Fuel System

A faulty fuel system can cause starting system faults in a Ford F150 because the starting system relies on a sufficient supply of fuel to operate properly. Clogged fuel filters, failing fuel pumps, or malfunctioning fuel pressure regulators can cause a lack of fuel supply to the engine, resulting in starting problems.

For example, if the fuel pump is not providing enough fuel pressure to the engine, it may struggle to start or may not start at all. Similarly, if the fuel filter is clogged, it can restrict fuel flow and prevent the engine from starting.

Diagnosis: Inspect The Fuel System

To diagnose a faulty fuel system, you can perform an electrical test or a fuel pressure test. Here’s how to do this. 

Electrical Test

To perform an electrical test, start by checking the fuel pump fuse and related fuses for signs of being blown and replace them if necessary. The fuel pump fuse is located under the hood within the fuse box. Then, check the voltage at the pump itself to ensure it’s getting power. In the Ford F150, this fuse is fuse typically labeled as 50 and the rating is 30A.

If the fuel pump is not receiving power, check the fuel pump relay circuit. If everything appears to be working electrically, perform a drop test using a voltmeter. If there is more than a one-volt difference, it could indicate corroded wires or circuit issues. 

Electrical System Testing

Fuel Pressure Test

You can find the fuel pump test point, which is usually near the fuel injectors, and locate the point at which the pump hooks up with the filter injector rail. There should be a separation joint or a test port, where the pressure gauge attaches. Different gauges may have slightly different instructions, and the location of the fuel pump varies from vehicle to vehicle, so consult your owner’s manual for more specific instructions. 

Let the engine warm up slightly, then check the pressure both at idle speed and at the rated speed listed in your pump specifications. If you don’t know the rated speed, just rev the engine and see how the pressure reacts. The pressure should match the specifications listed in the repair manual

Solution: Fix The Faulty Component of the Fuel System

Depending on the diagnosis the fixes of the fuel system can vary. However, the fuel system is one of the most crucial parts of the vehicle. In this case, an automobile mechanic is the best person to fix it. The average cost of a Fuel Pressure Test is between $44 and $55 depending on the car.


Why Won’t My Ford F150 Start But I Have Power?

If the engine holds compression well, and the fuel system is working correctly, but it still won’t start, that tells us that your Ford F150’s spark plugs may not be working. The spark plugs ignite the air/fuel mixture inside the engine’s cylinders, and if they are worn or fouled, they won’t produce the necessary spark to start the engine.

Can A Bad Starter Solenoid Drain A Battery?

Yes, a bad starter solenoid can drain a battery. In fact, repeatedly attempting to start your car with a faulty starter can drain the battery even faster. Additionally, a faulty starter is a leading cause of battery overcharging, so it’s important to pay attention to your vehicle regularly and learn the symptoms of a bad starter to prevent these issues from spiraling out of control.

How Do I Know If My Starter Is Draining My Battery?

To test if your starter is draining your battery, try starting the engine and listen for a humming sound followed by a click. If you hear it, check the battery by disconnecting the terminals and turning on the car’s lights. If they are dim, the battery is the problem. If they are bright, tap the starter lightly with a hammer or wrench and try starting the car again. If it still fails, the starter is likely draining the battery.


Well, this concludes the whole explanation regarding starting system fault Ford F150. Hopefully, this will be enough to get rid of the issue you’re facing with your starting system. 

However, if you feel these procedures are challenging for you, it’s better to have them fixed by an automobile professional. 

Thank you!

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William Baldwin

This Is William Baldwin, The Founder & Managing Editor of this website. Me and my team share automotive tips, tricks, and news

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Talha Atta

Talha Atta, a Mechanical Engineer and experienced technical content writer and editor at with a passion for the automotive industry.