Q: 2012 Jeep Grand Cherokee replaces altanator, still won’t start. Brake seems locked

asked by on October 17, 2017

Long story short, battery light came on while driving. Tried to make it home, jeep died. Had it towed. Replaced altanator, charged the battery overnight. jeep will turn on now, but won’t start. Brake feels really tight when I press it to try to start it.

My car has 103335 miles.
My car has an automatic transmission.

Battery will not hold a charge Inspection $79.99 - $99.99 Get a Quote

The brakes may feel stiff prior to starting the vehicle as the vacuum that exists in the brake booster when the vehicle is running may decrease when the vehicle is not running. Once the vehicle starts, the booster replenishes the vacuum assist and the brake pedal should feel normal again.

The issue of the vehicle not starting after charging the battery or after it sits for a period of time may suggest a failing voltage regulator that could be allowing the alternator to supply too much or too little amperage to the battery resulting in the battery never maintaining a consistent charge as it is designed to. The voltage regulator is a unit that regulates the charging of the battery by the alternator. When the voltage regulator is not working properly, this may result in the alternator allowing too much power to be delivered to the battery resulting in damaging wires and prematurely sometimes destroying the battery. A common sign of this is usually the acid inside the battery boiling causing the battery to swell. You may also smell a bit of smoke due to things potentially getting too hot. 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. I would recommend having an expert from YourMechanic come to your location to diagnose your vehicle’s charging system.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing


Experienced Mechanic?

Earn up to $70/hr

What others are asking

Stereo turns off and lights flicker when I turn up the volume on the stereo.

Hi there. If you have a factory radio, then the volume knob switch is shorting out with the radio controls causing the radio to shut off and flicker the lights. If you have an aftermarket radio, then there could be...

Engine light and limp-home light

Hello, and thank you for writing in. When the vehicle's check engine light and limp mode are both set off, there is a problem with the vehicle that needs to be addressed. You can easily clear the codes with a...

Heater blows cold when temp gauge is halfway. both heater core hoses are hot.

If both heater hoses are hot then the core is getting hot coolant flowing through it. You should check the temperature blend door actuator behind the glove box on heater case to see if it is operating the temperature blend...

Idling low at 1 to 1.5k rpm. can not get rpms above 3k.

It sounds like you may have a couple of different issues going on here. At idle your car should be hovering around 750-800 RPM's consistently. This is generally controlled by the idle air control valve which a valve that reads...

White smoke out tailpipe.

If there was oil splattered all over the bottom of the vehicle, there is a good chance that the smoke you are seeing may just be excess oil that is being burnt off of the hot motor and exhaust. To...

I just bought a new battery for my 2007 Cadillac STS. I got my alternator and starter checked and both came back good. What could

Hey there. Starting systems are very simple. If your issue relates to it, it can only be a few things. Let me start with having the starter tested. When you take a starter in to get 'bench" tested, the test...

Installing performance brakes

Hi, thanks for writing in. It all depends on the performance parts that are being installed. You suggest following the recommendations of the kit manufacturer. If the rotors and pads are the same size as the original equipment, then you...

All lights come on and the gages, radio, heater, window wipers don't work and car won't come out of park.

This is a known issue with the Chrysler Pacifica related to a shifter interlock mechanism that sits down in the shifter console. This is a small plastic piece with a hook on the end of it connected to a spring....

I DROVE THRU A FLOOD & MY CAR STALLED. NOW THAT IT STARTS ITS KNOCKING... WHAT CAN BE CAUSING THIS?

If you drove through deep water, chances are your engine took in some water and did internal damage to it. When engine suck in water, they cannot compress the water that gets into the cylinder, so it usually locks up...

Related articles

A Buyer's Guide to the 2012 BMW X3
If If you like high-end SUVs, the 2012 BMW X3 is definitely worth taking a look at. It’s a great mixture of luxury, utility and convenience. Key Features The Servotronic power steering on this SUV is excellent for giving you...
The Best Used Cars to Buy If You Live in a Cold Climate
If If you live in a cold climate, likely one of your biggest concerns when you are considering which used vehicle you should buy is how well it will perform in snowy, icy conditions. We have evaluated a number...
A Buyer’s Guide to the 2012 Chevrolet Corvette
The The Chevrolet Corvette is an American original that has stood the test of time. With the 2012 version, you’ll discover improved handling and horsepower that delivers the superior performance you’ve come to expect from this icon. With options as...