Need new battery.

ANSWER : This may be a sign of a failing voltage regulator or potentially a bad grounding problem causing a draw on the system. The voltage regulator is a unit that regulates the charging of the battery by the alternator. Often times this will result in the alternator allowing too much power to be delivered to the battery resulting in damaging wires and prematurely sometimes destroying the battery. In other cases it may result in the alternator not supplying enough power to the battery, resulting in undercharging the battery or not charging it at all. In either case, I would recommend having an expert from YourMechanic come to your location to diagnose your vehicle’s charging system.

ANSWER : Hello, thank you for writing in. If you are not able to get the starter to turn over or make any noise what so ever, then you need to start by checking the power supply to the starter solenoid. If it has a full 12 volt power supply available, then you are having either electrical or mechanical issues with the starter or the new solenoid. It may even need to be shimmed so that the gears are aligning correctly. If you do not have a full 12 volts available at the starter, then you need to trace down the electrical fault. You can start at the battery or the starter, and trace back until you find where the voltage from the battery drops off. There in lies your problem. For more help with this testing, contact our service department to schedule an appointment.

ANSWER : Hello – it is NOT likely your spouse damaged the battery during the swap. Far more often, the electrical energy in the battery would fry wiring or other electrical components if something is mis-connected. More than likely, the battery swap has caused a security mechanism to disallow starting. These security systems are designed to interpret "no electrical power, power re-established" as the car being stolen, so disable the ignition. I would recommend an electrical inspection by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

ANSWER : Your car should have two batteries. One for cranking and one for operating the body accessories. If you didn’t get ample warnings on the dashboard of upcoming problems, then there is something else wrong with the car. That said, as you have guessed, replacing a battery is not what it used to be and there is a certain amount of special knowledge and equipment that is necessary to get the job right. But that knowledge and equipment is not exclusive to the dealerships. Many of the Your Mechanic technicians have the equipment and the know how for this particular job. Depending on the who is in your area you may be able to get the job done right there on the spot. Click the link and fill out the form to Have a technician come to your home and check out your car and determine if there is a Mercedes specialist in your area.

ANSWER : Hi there. The only thing that I could think possible is causing your problem is that something may not have been correctly installed while your son was completing this maintenance. However, if your engine was difficult to start before this service, it’s possible there are different components that are damaged that simply didn’t resolve the issue. The only way of knowing what is going on with your Trailblazer would be to have one of our mobile mechanics in your area come to your location and complete a car is hard to start inspection.

ANSWER : The diagnostic test that is typically used to determine if a battery is good or bad is the "load test". YourMechanic can perform such a test in the field, and if your battery turns out to be bad, a certified Mechanic can replace the battery. Only fully charged batteries can be load tested. If it turns out your battery is good, but it is not maintaining voltage in use, there could be a problem with your car’s charging system. At the same time that your battery is tested, YourMechanic can test the output of the charging system. If the battery tests good and the charging system output is within specification, and yet the battery light is still on, there could be a short, or excess current draw on one of the circuits served by that battery. Regardless of what the problem is, if you set you a diagnostic with YourMechanic a certified professional will resolve this problem for you.

ANSWER : Hello.

If replacing those particular components did not correct the issue then the next thing I would look at is the vehicle’s voltage regulator. It appears that this engine’s electrical system is equipped with an external voltage regulator that functions, or malfunctions, independently of the alternator. The voltage regulator regulates power from the vehicle’s alternator, and can cause issues with the electrical system when it malfunctions. I would test it to see if it is functioning properly. It is a silver box that should be mounted somewhere in the engine bay, usually on a wheel well. A technician from YourMechanic can come to your home or office to replace your car’s voltage regulator if necessary.

Regards,
Eduardo

ANSWER : Hello.

A crank but no start condition can be caused by many things. A few common causes are a faulty crank position sensor, or issues with the fuel system. The crank position sensor is used in the engine’s fuel calculations, and in some cases it’s failure will disable the engine.

It may also be possible that there is issues with the fuel system that are preventing the engine from running. If the fuel pump or injectors have an issue the engine may not run correctly, or at all. It may also be possible, for either case, that the issue may be wiring related.

I would start by trying to determine if the engine is getting fuel and then going from there. If you need assistance with these checks, consider YourMechanic, as one of our mobile technicians can come to you in order to diagnose your starting issue firsthand for an accurate repair.