Mercedes Alternator Diagnostics From The Driver's Seat

[@FamilyTraveler23]

Ladies need these videos.I have GL450

[@BUR70713]

Dude, I love your Channel, I have a 2004 G55 AMG, I am trying to get the alternator out of the dang thing! Any advise on how to do this?

[@iRepairAutos]

Try taking it out from beneath. Often the radiator has to come out.

[@BUR70713]

iRepair Autos you are correct the radiator had to come out!

[@wayaboveme]

Have you ever had a vampire drain on your battery? I put a new battery in and both alternator and starter test fine but every time I start the engine, it takes just a split second too long to crank over and if I leave it for a few days, it takes even longer. Gotta believe I have a small current leaking out somewhere on my 2009 ML 350 4matic but don't know hot to go about finding this. Can you help on this or even do a new video on this subject? Thanks! Will (BTW, glad you also recovered from COVID. I was in the hospital for a week on the first go-round and was touch and go...).

[@lamarmc]

I've got this problem now. What was your problem?

[@LOCKBROWN1]

Good Morning. In your opinion, what is the best Mercedes SUV? Do you prefer diesel or gasoline?

[@js-amg]

LOCKBROWN1 I would suggest petrol here. Less hassle and less expensive relating to parts eg. glow plugs, injector pumps. That dreaded DPF filter that need regenerating or replacing when it gets blocked at over a grand plus labour to do it. AD Blue for the diesel emissions plus gas as well. You’d have to weight it all up comparing gas mileage. But all those parts mentioned there’s a lot of gas you can purchase as well... Vehicles. I’d suggest the GL class. Every man and his dog has an ML or similar here in KZbin and people don’t chat about or even share info much on the GL’s for some unknown reason. The GL is Roomy and great on the airmatic suspension 7 seats if you want. I have an AMG GL class and it great for us as a family. Good on gas too. It’s has the occasional opps. But 35ys as a senior tech it’s not a problem for me. I just use the keep it simple when diagnosing and you can do it too. Don’t let the badge scare you. Cars are car no matter what they are.. hope it helps my friend...

[@LOCKBROWN1]

@@js-amg Thanks for the explanation and I agree with you about the maintenance being more expensive. Really much more expensive.

[@js-amg]

LOCKBROWN1 anytime my friend..

[@2Mont106]

Hey iRepair Auto, were you able to get back with Carlis on his question about P0304 #2 misfire? Reason being is that i'm going through a random misfire (P0305/P0300 code permanently) that's primarily showing up as a cylinder #5. I'm thinking a faulty injector (cylinder#5) to be the culprit being that. Reason being is because every time i get on it on the freeway the check engine light will come on. Now i'll pull over, shut the engine off, start it back up and the check engine light will go off...until i get on it again. I hear that the problem can range from multiple sources but the one thing that stands out to me is i can tell that i'm losing some compression from somewhere noticeably when i break stall the car in reverse. it just kind of bogs. I ran these diagnostics through my scanner-MB2 (eg. Intake manifold Absolute Pressure 29.0 kPa ,AFR from Mass Flow Sensor 4.66 g/s, and Fuel Rail Pressure 380 kPa) and really don't know what to make of these readings,as far as set points go, seeing that i'm totally new to the foreign car experience.

[@brucey7177]

Probably not. Looks like he doesn't reply to questions

[@js-amg]

Lamont Neal Jr. Well to help you. You have a random misfire.. Ok let’s try to isolate that cylinder. First I’d look to get an injector noid tester. It plugs in line between the injector and the wiring plug and it lights up as the car runs. If it misfires you’ll see the light flicker with the misfire and it will show it’s an injector fault or wiring fault to the injector. I”d also change the spark plug to confirm it’s not a silly plug. If it doesn’t fart on the other cyl then it’s not plug. Now as the car is ideling over. Have a friend raise and lower the revs and at the same time wiggle the wiring harness to see if anything happens. Also spray contact cleaner into the connection plugs of the injector and the coil pack unit. You should be able to find online the resistance levels for the coil pack. Like plug leads 8000ohms per foot using a multi meter. As you check wiggle the Flexi plug tube and see if it’s changing the resistance. I wouldn’t suggest a fuel pump or fuel rail pressure as it’s one cyl only. Possible blocked injector could be. The injector would have a filter basket and you have to remove the whole lot to do that. But first thing is isolate and confirm either injector or plug and coil pack.. while it’s running spray some light water on the coil pack. Sometimes they can have a hairline crack on the top that can cause a miss as well. Also spray some carby clean or brake clean around the inlet gasket as well. But do it lightly and be careful If the engine rises there’s a leak there. Also check the throttle body that it’s not loose and it’s sealed well with the air filter unit. Check all vacuum hoses too with carby clean as well. let me know hope it helps...

[@slonecapone]

Hello, I have a 2007 E350 and i have changed the alternator and the battery, but my battery keeps draining. I just replaced the both the right and left headlight assembly and that did nothing. my wife came home and told me that my driver side lights were on but it was only the parking light. How can I fix this problem. i would really appreciate the info.

[@panseycain7086]

Hey, How do you diagnose a bad water pump or a serpentine belt? Thanks

[@jasonjewsbury8320]

I really need your help diagnosing an intermittent electrical issue.

[@brucey7177]

I'll attempt to ask for the third time with no reply so far. Off this subject but I have a 2004 E320 and the drivers side speakers stopped working. Any idea what it could be and how to fix?

[@iRepairAutos]

Have you checked my video on radio reset? Start with that procedure. kzbin.info/www/bejne/n6i1eoiEgtKMjqs

[@js-amg]

Mmmm that’s just shows battery volts not actual alt volts as it’s written. It doesn’t split bat or alt volts. The best solution is using a multi meter direct off the alt and then off the battery. If the alt say 14.1 and bat says 13.5 there’s the fault. Possible dead cells and you’d then load test the battery to confirm. You can also do a continuity test on the battery to see what’s draining the battery with the same multi meter if you think the battery is being drained as well. Scan tools are great but they will lie to you and trap you out if your not careful. Go back to the basics in diagnosis. KISS method here. Keep It Simple Stupid no matter what car you have and 5 computers to run it, it’s still gas and spark that makes any car run!