Jake78

Hi, I own a 2000 E320 4Matic. For the last couple summers my AC has been slightly out of sorts. I've been resetting the error codes to get the compressor to kick in and blow cold air. I've done it a few times. Once I do it I usually don't have to again for the remainder of the year. The other day I reset the codes, removed the key, placed it back in the ignition and attempted to start the car. It kinda of did a split second crank and then made a sound like a fuse shorted. The AC was kicking cold air, but now the car won't even attempt to start. It doesn't crank, turn or anything.

For reference, the error code I get is b 1416, which is the Coolant Pump Motor.
My battery is nearly brad new.
The vehicle is up kept and in good condition. No overheating or anything of that nature.

If anyone has any idea on what may be going on I'd like to know. Thanks.

Plutoe

Does the starter turn when you apply voltage directly to the starter!

Jake78

I'm sorry. I haven't applied voltage directly to it.

Jake78

What is the particular tool or device used to do that with?

Plutoe

If you are doing this on the lawn---try jumper cables

kajtek1

Display car voltage on climatronic and then turn all the headlights and blower to high.
Notice voltage change.

Jake78

As far as monitoring voltage through climatronics, the only voltage reading I could get was the Battery Voltage (Aside from the Blower Control Voltage, which was normal). It read my voltage as 11.2 V, and 10.5 V with the blowers on full and my Brights on. I measured the battery directly and it read around 12 V. I know its supposed to be between 12.4 and 12.6. I tried jumping the car for about 10 minutes, no change. I put in a new starter relay as well. I saw that you could test the voltage to the starter by accessing the solenoid cable, but my starter looks extremely difficult to get to and I can't find an in depth guide for my model.I'd really like to get it off and test it as well.

kajtek1

12V is weak battery. How did you try to jump it? You need #2 cables for good jump.

Jake78

Just the standard method I guess. Battery to battery. I let it charge for nearly ten minutes. Do you think 12 V is enough to start the vehicle? It seems strange if it were the battery to just all of sudden not be able to start the car with no signs of being low at all. Also no instrument dimming or partial cranks. I thought that it might be something related to me trying to get the voltage to the ac compressor. Either way I'm gonna take the battery to Autozone and get it checked out since its only a month old (It would be a godsend if the battery was the problem). Do you know what the best way of going at the starter would be, as far as removing things to get to it. I can't find anything for the 4matic that is useful?

kajtek1

This is computerized car.
Once computer sense low voltage - it will never start the starter.
Testing the battery is tricky, but Autozone has big machines that have decent program for it.

Jake78

Had it tested today. The guy up front apparently didn't do any initial tests on it, just hooked it up to the charger. Either way, it charged for over 30 minutes and the worker who I got it back from told me that the charge was 900 and the voltage was 12.96 V. The Benz is still no crank no start though.

kajtek1

He hooked it up to charger after you charged it?
Something very strange went there and voltage with no load right after charging is meaningless.
You need to get somebody who knows batteries to test it.

Jake78

I didn't charge it. He took it and immediately hooked it up to the charger without taking any initial readings evidently. So we don't know what the voltage was and how low it was at the time. I guess I could take it to another Autozone and see what they do. At this point though I don't think it has to do with the battery itself since it still won't start with proper voltage.

kajtek1

And where did you have proper voltage? Your reports never show it?

Jake78

As far as battery voltage goes a 12.96 should be good, right?

kajtek1

You need to google how batteries work and try to understand.
Battery voltage short time after disconnecting from charger is meaningless.
You can buy load tester and do real test if turning your lights is too difficult.

Jake78

Ok, what am I missing? If the battery is 100% charged and the voltage is above the required amount when I hook it back up, when I physically test it with my multimeter, what else is there that is preventing the computer to start the car?