Check Engine Light and Battery Light On? Here’s What to Do When Your Car Won’t Start

If your car won’t start and you notice that both the check engine light and battery light are illuminated, then it’s likely that one of two things is happening. The first is that the battery is dead or malfunctioning, in which case it needs to be replaced. The second is that the engine has a problem, such as a faulty spark plug or fuel injector, which needs to be serviced by a mechanic. In either case, it’s important to diagnose the exact cause of the issue before attempting any repairs, as this will ensure that you don’t do any unnecessary work or damage to your car.

Common Reasons Why a Car Won’t Start

When a car won’t start, it can be due to a variety of issues. It is important to identify the cause of the problem in order to get the car going again. The most common reasons why a car won’t start are due to a weak or dead battery, an alternator problem, an issue with the starter motor, or an issue with the ignition system.

Diagnosing a Car Won’t Start Issue with Check Engine Light and Battery Light On

In order to properly diagnose why a car won’t start when both the check engine light and battery light are on, it is important to have access to diagnostic tools such as OBDII scanners and oscilloscopes. These tools allow for verification of electrical connections and components, analysis of sensor data from the engine computer, and inspection of fuel system components.

Checking the Battery for a Car That Won’t Start

One of the first steps when diagnosing why a car won’t start is checking the battery. This can be done by testing the voltage output with a multimeter tool. It is also important to inspect battery terminals for corrosion or damage, measure specific gravity of electrolyte solution in lead acid batteries if applicable, and ensure that proper charging voltage is being applied to each battery cell.

Checking the Alternator for a Car That Won’t Start

If there are no issues with the battery then it’s time to check the alternator. This involves testing alternator output voltage with a multimeter tool as well as inspecting wiring harness connectors for signs of damage or corrosion. Additionally, AC voltage output can be measured with an oscilloscope tool if necessary.

Checking the Starter Motor for a Car That Won’t Start

The next step in diagnosing why a car won’t start is checking out the starter motor. This involves testing starter motor circuit continuity with a multimeter tool as well as verifying solenoid engagement when ignition switch is activated. Additionally, it’s important to inspect starter motor drive gear engagement as well as measure armature resistance on occasion if necessary.

Checking the Ignition System for a Car That Won’t Start

When you find yourself in a situation where your car won’t start, it’s important to take a systematic approach to troubleshooting the problem. One of the first things to check is the ignition system. Testing coil pack resistance with a multimeter tool, inspecting spark plug wires for damage and corrosion, verifying camshaft position sensor signal output, and confirming crankshaft position sensor trigger signal are all important steps in diagnosing a car that won’t start.

Testing coil pack resistance enables you to determine whether or not the ignition system is supplying enough power to fire the spark plugs. This can be done with a multimeter tool by measuring voltage across each coil pack terminal. If there is insufficient voltage, then it could be an indication of an issue with the coil pack or spark plug wire.

Inspecting spark plug wires for damage or corrosion can help to identify whether or not they are providing sufficient current to fire the spark plugs. It’s important to check for any visible damage such as cuts or tears in the insulation of each wire, as well as any signs of corrosion on the metal connectors. If there is any visible damage or corrosion, then it may need to be replaced before proceeding further.

Verifying camshaft position sensor signal output will help you determine whether or not the engine is receiving enough information from this vital component in order to run properly. This can be done by using a scan tool and checking for an appropriate signal from the camshaft position sensor while cranking over the engine. If no signal is present, then it could indicate that there is an issue with either this component or its wiring harness.

Finally, confirming crankshaft position sensor trigger signal can help you diagnose whether or not this component has failed completely. This can be done by measuring voltage at each terminal of this sensor while cranking over the engine with a multimeter tool. If there is no voltage present at either terminal then it could indicate that there is an issue with either this component or its wiring harness.

Troubleshooting Fuel System Issues on a Car That Won’t Start

Fuel system issues are another common cause of cars not starting properly, so it’s important to take steps to diagnose these potential problems as well when troubleshooting your vehicle’s starting issues. Checking fuel pressure and volume from your gas tank by connecting a fuel pressure gauge will tell you if your fuel pump is providing adequate fuel flow for your engine. You should also test fuel injector pulse width and spray pattern using a scan tool in order to make sure that they are delivering proper amounts of fuel into each cylinder during operation. Lastly, measuring air intake temperature and manifold pressure will tell you if your engine has enough air entering it during operation in order to achieve optimal combustion efficiency levels required for starting up properly.

Analyzing Computer Data When Check Engine Light Is On

If your check engine light has come on while trying to start up your vehicle, then it may indicate that there are some issues with one or more of its computer modules which need addressing before attempting further diagnosis of starting issues. Using scanner tools such as OBD-II readers can help you read what trouble codes have been stored within module memory which may provide clues as to what needs further attention on your vehicle’s computer components in order for them all work together correctly during startup sequence operations such as ignition timing and fuel injection control functions which can affect starting performance negatively if something goes wrong during these processes due improper module communication between one another.. Additionally, comparing sensor inputs versus manufacturer specifications listed within service manuals can provide you with valuable information regarding what values should be expected from various sensors during normal operation conditions which will again help when trying pinpoint why certain functions aren’t working correctly throughout startup operations on vehicles equipped with electronically controlled engines systems such as those found on most modern day vehicles today.. Lastly ,reviewing live data streams from individual modules can also provide helpful information when trying identify potential errors occurring within certain components during startup procedures due software bugs ,low voltage supply issues ,or other electrical failures occurring within certain components connected vehicle’s electronic control unit (ECU).

Common Causes of Battery Light Illumination on Dashboard

A battery light illumination on dashboard usually indicates that something isn’t right electrically within your vehicle’s electrical system which could lead starting problems once again depending upon severity of problem detected by onboard diagnostics system (OBD). The most common causes include dead or dying lead acid battery cell capacity ,faulty alternator not charging battery properly ,or low vehicle voltage due high resistance cable connections causing excessive heat generated when attempting start vehicle due lack sufficient power running vital components such increased starter motor draw . To ensure proper diagnosis ,it’s recommended use test light probe measure current passing through cables connecting both battery terminals ensure adequate current flowing prevent any potential short circuits occurring due poor connections between both terminals . Additionally ,it would also wise conduct visual inspection around alternator belt assembly well main ground connection points chassis body ensure all connections tight secure prevent any possible loose connections occurring due vibration caused whilst driving .

Resolving Electrical Issues on Vehicles That Won’t Start

In addition checking ignition system troubleshooting fuel system issues analyzing computer data ,it’s also essential resolve any electrical issues preventing car from starting up properly . Identifying open shored circuits wiring harness replacing damaged relays fuses power distribution box repairing poor ground connections between chassis body components should all taken into consideration when attempting diagnose causes non-starting vehicles part fault finding process . Using digital multi-meter test continuity between both positive negative cables connected battery terminals inspect connections fuses controlling starter motor relay ensure current flowing through circuit without interruption . Additionally ,checking wiring harness connecting ECU main fuse box also recommended ensure all have been securely attached prior attempting start up car again avoiding risk short circuit affecting performance . Finally don’t forget inspect alternator belt tightness condition make sure hasn’t slipped off pulley wheel causing lack traction generate electricity charge battery back full power ready next journey ahead

FAQ & Answers

Q: What are the common reasons why a car won’t start?
A: The most common reasons why a car won’t start include checking the battery, checking the alternator, checking the starter motor, and checking the ignition system.

Q: What tools are needed for troubleshooting a car won’t start issue with check engine light and battery light on?
A: Diagnostic tools needed for troubleshooting a car won’t start issue with check engine light and battery light on include a multimeter tool, an oscilloscope tool, and a scanner tool.

Q: How can I check the battery of my car that won’t start?
A: When checking the battery of your car that won’t start, you should test the battery voltage output with a multimeter tool, inspect the battery terminals for corrosion or damage, measure the specific gravity of electrolyte solution in lead acid batteries, and ensure proper charging voltage is applied to battery cells.

Q: How can I resolve electrical issues on vehicles that won’t start?
A: To resolve electrical issues on vehicles that won’t start you should identify open or shorted circuits in wiring harness, replace damaged relays or fuses in power distribution box, and repair poor ground connections between chassis and body components.

Q: What are common causes of battery light illumination on dashboard?
A: Common causes of battery light illumination on dashboard include dead or dying lead acid battery cell capacity, faulty alternator not charging battery properly, and low vehicle voltage due to high resistance cable connections.

In conclusion, when a car won’t start and both the check engine light and battery light are on, it is important to take the car in for service as soon as possible. The check engine light can indicate a wide range of problems, from something simple like a loose fuel cap to something more serious like an exhaust leak or faulty spark plugs. The battery light can indicate an issue with the alternator or other components of the charging system. In either case, it is important to get the vehicle checked out by a qualified technician as soon as possible in order to ensure that the problem is properly taken care of.