Grab a voltmeter. After the car has been off for several hours, measure the battery voltage without starting the car.

Anything less than 12.6V is a discharged battery. Charge it up. If this does not fix the problem (still have slow or no start), measure battery again.

If it again shows not fully charged, replace the battery. If it does show full charge, get it load tested at any local parts store you would buy a battery from. If load test fails, replace the battery.

A load test is the gold standard for testing a battery, a voltmeter can sometimes prove a battery is bad but can not prove it is good. Only a load test can prove a battery is good.

If the battery passes load test (or fails and you have a new battery) and you still have the problem, then further troubleshooting can proceed. Most problems matching your description are the battery. Need a solid battery both to find and correct any remaining possible problems. To say this another way, these cars are based on Mercedes tech and need a solid battery both to run right and as a foundation for troubleshooting.

 

The key to the problem is that it started with the remote. When in remote mode it's goes to key on, checks all systems, pauses and they starts. During that pause the fuel pump runs. Since it no longer starts with the remote, that tells me that your fuel pump has now completely failed.

There is a chance that it could be battery related so that is worth checking into, all the hard stars could have taken it out by now.

 

The key to the problem is that it started with the remote. When in remote mode it's goes to key on, checks all systems, pauses and they starts. During that pause the fuel pump runs. Since it no longer starts with the remote, that tells me that your fuel pump has now completely failed.

There is a chance that it could be battery related so that is worth checking into, all the hard stars could have taken it out by now.

I am struggling with the OPs English. I am reading the word "sluggish" as slow cranking and the word "stay" as start. I am doing my best to accommodate what looks like a Spanish speaker making an effort to communicate.

Your interpretation may also be true, but until there is solid cranking speed (or sluggish cranking with a good battery), no point dividing out if a fuel or other problem, a starter or other problem, a recurring battery drain or poor charging killing the battery, ...

 

I think it’s how I’m wording it, I don’t speak Spanish. But the battery seems to be fine. When I drive the meter on the battery bounces from 12.5 to 14.

So to clarify my question. I would push the start button , it would be sluggish but would start.l so then I used the key fob and it seemed to start a little quicker. Now it doesn’t start at all . With the fob or by pushing the start Burton

 

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That is not very expensive and does the actual load test. I just let AutoZone do that and find something like this for $10 is fine for measurement and most electrical troubleshooting:

ANENG Digital Multimeter with Case,DC AC Voltmeter,Ohm Volt Amp Meter,Measures Voltage,Current,Resistance,Continuity,Diodes,Electric Tools for Househould Outlet,Automotive Battery Test: Amazon.com: Tools & Home Improvement

ANENG Digital Multimeter with Case,DC AC Voltmeter,Ohm Volt Amp Meter,Measures Voltage,Current,Resistance,Continuity,Diodes,Electric Tools for Househould Outlet,Automotive Battery Test: Amazon.com: Tools & Home Improvement

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I would use the extra money to buy a basic battery charger (I have been using a cheap charger for over 40 years) As soon as I get an AGM battery, I will replace it with at least this:

Amazon.com: NOCO GENIUS1: 1A 6V/12V Smart Battery Charger – Automatic Maintainer, Trickle Charger & Desulfator with Overcharge Protection & Temperature Compensation – For Lead-Acid & Lithium Batteries : Automotive

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But more likely this because I don't want to wait a week for a charge, a day will do:

Amazon.com: NOCO GENIUS5: 5A 6V/12V Smart Battery Charger – Automatic Maintainer, Trickle Charger & Desulfator with Overcharge Protection & Temperature Compensation – For Lead-Acid & Lithium Batteries : Automotive

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On edit: Considering any battery below 12.6V has some level of discharge (technically 12.7 for AGM, but a car will still start with 12.6V), charging is a matter of capacity and time. For someone in a hurry, a high rate of charge will get a battery going but might damage it.

A typical car battery has 80 amp hours of capacity. That means it can deliver 80 amps for an hour or 1 amp for 80 hours. In theory, with some real-world limits. But setting some real world tweaks aside, charging is the reverse. Pump in 80 amps for an hour or 1 amp for 80 hours to recharge an empty battery.

I have found (real world) a completely dead battery can rarely be saved, I do want to get a weak battery up to snuff in a few hours or overnight. I found about 4A is a good safe charge rate, and the 5A Noco (Genius 5) is smarter than my dumb charger from nearly a half century ago. If I want to get going right now, a jump start will usually do it, the next stop for me then is AutoZone because I'm probably buying a battery. Exception would be if I know a good reason for a dead battery like leaving the headlights or even dome light on.

 

Welcome to Challengertalk "When I drive the meter on the battery bounces from 12.5 to 14 "

This might indicate the alternator stopping charging, or a loose connection? That would only address your starting problem if the battery voltage is low when starting though I'd think

When you say it doesn't start at all, does it crank?

A Guy

 

So to clarify my question. I would push the start button , it would be sluggish but would start.l so then I used the key fob and it seemed to start a little quicker. Now it doesn’t start at all . With the fob or by pushing the start Burton

OK, so follow the suggestion in post #2. Grab an actual voltmeter ...