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rjmcq
12-08-2014, 04:10 PM
Car has no power to anything. Put new battery in and still nothing. Can jump start car and it will run with many warning lights on. Any suggestions?
Thank you,
Bob

AMGTesTDriverNJ
12-08-2014, 04:19 PM
Maybe check to see if you still have an original wiring harness?

gerryvz
12-08-2014, 04:26 PM
What kind of car is it?

rjmcq
12-08-2014, 06:22 PM
What kind of car is it?
Harness was changed not sure when. 1994 E500. Thanks,

gerryvz
12-08-2014, 06:51 PM
Please fill out your profile with your general or specific location, as it will help people identify local resources to help you.

Three things to check, before you go much further:

First, check all of your fuses in the fuse panel to make sure that they are all working. That means, rotate each one with your fingers in its socket to make sure it is passing current and is not broken.

Second, make sure that both wires are firmly and well connected at the battery's positive terminal. The smaller (+) wire is a direct power connection to the car's computers in the CAN box underhood.

Third, if you are able, please pull codes from the car's computers via the 38-pin connector in the CAN box. If you cannot do this yourself, please bring the car to an independent shop that can perform a comprehensive code scan. Have them clear the codes and give you a print out of what the codes are that they pulled. Then, if you are able, drive the car and see what codes come back.

If the first two items check out OK, then it sounds potentially that the car's charging system may not be working. I would consider the voltage regulator as a potential problem for this, at least for a first place to concentrate.

With a new/fully charged battery, you should be able to start the car and run it (it will run for at least a little while off of the battery). This should allow you to pull the codes (you can also pull codes without the engine running, but with the key in the "accessory" position.)

Cheers,
Gerry

Klink
12-08-2014, 07:19 PM
All good advice above, except that note when Gerry said "accessory" position, I think he actually means the "run" position, simply with the engine not running (?). In other words turn the key clockwise as far as you can without actually cranking the engine.

Clean the insides (females) both of your battery cables using appropriate steel wire brushes. Make sure you see shiny bare metal inside each of the terminals. If you placed a new battery in the car and it did not start, and then you jumped it and it did start, you need to triple check the small additional positive wire that attaches to the positive battery terminal. If you have even the slightest doubt about the electrical properties of that connection, then just disassemble that connection, carefully inspect it, and the clean or repair it as required. You are describing classic symptoms of battery terminals with poor contact.

gerryvz
12-08-2014, 07:31 PM
All good advice above, except that note when Gerry said "accessory" position, I think he actually means the "run" position, simply with the engine not running (?). In other words turn the key clockwise as far as you can without actually cranking the engine. Let me clarify. In referencing the "accessory position," I meant the position that the key springs back to after it is turned all the way to the right to start the car. Even if the car does not start/is not running, this "spring-back" position should have all of the car's systems energized (computers, climate control system, etc.) -- if there is, in fact, enough power in the battery to energize them -- and allow the car's diagnostic codes to be pulled.

rjmcq
12-08-2014, 10:22 PM
Thank you for the suggestions I will try the suggestions as soon as the rain stops and let you know.

rjmcq
12-12-2014, 10:25 PM
The trunk light was stuck on due to a problem with the latch. Thank you for the advice.
Bob

gerryvz
12-12-2014, 10:33 PM
Glad you found the problem ! :goodjob: