It's like sitting Automotive school again and learning new techniques, never stop learning! Great videos, I've been watching your videos two to four times a week.
In my shop this week I have a Mercedes SLK 1.8 less that 5000 miles 9 years old Same engine same fault on cyl 3, thought it could be the control unit, but not sure, I have checked everything like you have, but didn't have the confidence to call the module. but having watched this fabulous video I'm calling it bad! thanks for the great diagnostic approach and content, keep up the good work.
Make sure to test all the coils by substituting them in another order, then clear the codes and re-read codes to assess whats unfolding? remember also to do the compression gauge test and cylinder leak down test to establish whether the Head Gaskets good.
That's one problem with today's cars is everything is so expensive. If it was a $30 part you don't mind trying it on a whim. But when parts can exceed $1000, you need to make sure you have it figured out. Been there many times with you on that.
Old school Mercedes used to be simpler and straightforward when they used an external ignition Amplier bolted next to the Coil, and older still in the day of Point,Condenser, rotor arm, and Dizzy caps, with Leads to each Plug, usually 1 of the leads or the King lead with the rotor arm defective. Nowadays any circuitry problem it then becomes big Dollar's and often a trip to the Main Dealership. Thank you for this great Video, much appreciated 🙂
Do these three wire coils have a switching transistor inside of them? If that is the case, then the tougher part of the ignition switching is being done at the coil itself. Maybe this is some sort of software glitch where the module sets an error for a circuit issue.
@@burgegerm7878 The switching is actually done from the ECU via the pulse from the CKP (crank position sensor+ Cmp- camshaft position sensor) although it has a Live to the coil, no Live feed wire is ever used as a pulse to switch high energy ignition systems.
What you're talking about at 12:15 thereabouts is something that is very common with built in electronic diagnostics testing. Also called ATE - Automatic test equipment. Equipment manufacturers have to make the most of time to implement versus financial gain. Depending on the value of the electronic circuit board - do you spend time and money to implement a test down to the minutest level or just have a higher level report and end it there leaving the deeper maintenance to understanding the circuit or more experience faultfinding these problems ? Most sensors in automobiles are relatively simple as opposed to radio frequency equipment - example radars. The problem I see with automotive electronics is the amount of wiring and the number of connectors that are a solution looking for a failure. The one good thing is the robustness of the circuit boards. To the manufacturers credit, there are less failures with the circuit boards than there are with the sensors, harnesses and connectors. Add to that the unnecessary electronics that keep getting installed in every updated model. I'm all for electronic injection and that's where I'd stop. Everything else after that is unnecessary.
I just wish we weren't all seeing tired or broken German cars people just bought that need more work than they are worth. But man a good deal is hard to pass up. Doesn't sound right when you say it out loud. We just had a C250 with oil and coolant leaks, along with timing codes, customer only wanted to fix the coolant leaks so it was "drivable." Became upset afterwards that the engine still made valve train noise and the check engine light was still on. I wish they would turn repairs like these away if they can't be done correctly, you're being set up to fail.
My '84 chevy has been giving me the run-around with the starter solenoid for about a year. I finally isolated the problem to the firewall bulkhead connector.
@gigiesparza396 By connecting a heavy gauge (about 12AWG) jumper wire with ring terminal connected directly to the starter solenoid start terminal. By connecting the other end of this wire directly to the battery positive terminal, this engages the starter sonenoid. The purple conductor from the igntion switch goes through the firewall bulkhead connector. Well, engaging the ignition switch start position is supposed to apply battery current to the starter solenoid. Mind you this problem only occurred when away from home (and tools, such as car ramps), of course! Power (voltage) was going into the bulkhead under the dash but nothing was coming out the bulkhead into the engine harness (purple wire to starter solenoid). Thus the infuriating no-crank.
I'm starting to get the feeling some dishonest customers are going to your shop knowing very well how honest the shop is, they go in saying : "I'm wanting to get a simple starter changed/replaced" Then the next day I complain that my head gasket was blown after you touched my car, knowing damn well it was a pre-existing condition.
That stuff is actually kinda happening with old beater cars some customers like to drive around, I have witnessed it. Time for example: Car is over 20 years old and when there is a problem they bring it to a shop: Like let's say the blower does not work at all speeds, okay it's diagnosed as faulty blower motor resistor. Diagnosis and estimate repair cost is given to the customer, customer complains that the part/job is too expensive, when told that the price is what it is, they can find another shop to do it if they want to. Customer accepts the job.. That part gets replaced and customer is happy. Week or two goes by, customer comes back with different problem, now the brake pedal goes to the floor. Shop says they need to inspect the vehicle, to see what the problem is. Customer agrees, they inspect it and find out how rust has eaten away a brake lines from the rear of car, fluid is slowly seeping from the rotten pipes.. Customer is told what the problem is and what needs to be done. Then the customer flips out, complains about how the car was fine until this specific shop touched it and how they ruined his car. Customer is not willing to pay for repair and repeats that It should be done "under warranty". They are not willing to get the car towed to somewhere else, instead they keep on harassing about warranty and how the shop broke their car.
you Nailed dude, 100% we had an avalanche of these morons in the past 3 Years, simply put when the Shop guys honest, humble and accommodating, they take advantage!
My experience with Mercedes, just as a DIY'er: If the battery has been weak recently and you have a ton of codes, clear all the codes, and drive it for a few days. See which ones come back. Low voltage makes all the modules 'go crazy'.
Good diagnosis. I would have put new plugs in it and coil on cylinder one also as a precaution, unknown vehicle history. I have seen similar ecu faults caused by ecu drivers overloaded by old plugs/ over worked coil packs. Have you tried Picoscope? I find there captures better and the software easier to manipulate
Daily tip. You can’t disconnect coils on Renault engines as the coils are earthed to each other so disconnecting cylinder one (flywheel side of engine 🤷♂️) coil with un-earth cylinder 4 also makes reading codes very confusing lol Moral of the story is pull the coil up out the cylinder don’t disconnect when looking for a bad coil.
Great video. I am now wondering if you guys offer a "used car inspection service"? You wouldn't be able to discover every little issue a car has, or potentially has, but a thorough shop as yourselves may save a customer a lot of headaches down the road.
Honda turns the injector off quicker than any manufacturer I've seen. Of course cycling the ign will bring it back for testing but makes it tough when such a short period of time is given before happening again. I always wished there would be a scan tool function for disabling that protective strategy while diagnosing.
Thank you for all you do ! I enjoy watching your videos! I would love to see one on how to set up a basic oscilloscope and use it! I know you use one in several videos but you have been doing it for years and make it look so easy! I researched for videos and not found a good one!
Another moral of this story is that don't buy a Mercedes (or any "premium" branded model) if you can't afford to own one as ownership of them includes the required servicing expenses people!!
The windshield guy scanned my car for codes before he touched the windshield. He said he had been blamed for all sorts of problems after replacing the windshield.
People think a service is checking every nut and bolt in the car kind of thing, but if you change their wiper blades and the next day it conks out its your fault.
That particular ECM is KNOWN FOR LOTS OF TROUBLE and the dealer knows about it !!!!!! 1. The ECM wiring absorbs oil in parts of it. 2. The ECM fails from jump starts. 3. The ecm mosfets go bad for no reason. 4. The ecm loses programming for no reason and needs replaced. 5. The ecm can trigger false codes for no reason. 6. The ecm can hang up the transmission and cause horrible jerking or locking. It's a dam Mercedes and let me tell you something 😂, this is THE BEGINNING OF HER NIGHTMARES.
The powertrains seem to be the weak part, though the unibodies and interiors seem to be pretty good. I have seen some of these types of cars in junkyards in good condition, seems like a big waste. Would be nice if people can just change out the powertrains for something simpler, like a toyota engine or something like that.
It's like sitting Automotive school again and learning new techniques, never stop learning! Great videos, I've been watching your videos two to four times a week.
In my shop this week I have a Mercedes SLK 1.8 less that 5000 miles 9 years old Same engine same fault on cyl 3, thought it could be the control unit, but not sure, I have checked everything like you have, but didn't have the confidence to call the module. but having watched this fabulous video I'm calling it bad! thanks for the great diagnostic approach and content, keep up the good work.
Make sure to test all the coils by substituting them in another order, then clear the codes and re-read codes to assess whats unfolding? remember also to do the compression gauge test and cylinder leak down test to establish whether the Head Gaskets good.
That's one problem with today's cars is everything is so expensive. If it was a $30 part you don't mind trying it on a whim. But when parts can exceed $1000, you need to make sure you have it figured out. Been there many times with you on that.
Old school Mercedes used to be simpler and straightforward when they used an external ignition Amplier bolted next to the Coil, and older still in the day of Point,Condenser, rotor arm, and Dizzy caps, with Leads to each Plug, usually 1 of the leads or the King lead with the rotor arm defective. Nowadays any circuitry problem it then becomes big Dollar's and often a trip to the Main Dealership. Thank you for this great Video, much appreciated 🙂
Do these three wire coils have a switching transistor inside of them? If that is the case, then the tougher part of the ignition switching is being done at the coil itself. Maybe this is some sort of software glitch where the module sets an error for a circuit issue.
@@burgegerm7878 The switching is actually done from the ECU via the pulse from the CKP (crank position sensor+ Cmp- camshaft position sensor) although it has a Live to the coil, no Live feed wire is ever used as a pulse to switch high energy ignition systems.
What you're talking about at 12:15 thereabouts is something that is very common with built in electronic diagnostics testing. Also called ATE - Automatic test equipment. Equipment manufacturers have to make the most of time to implement versus financial gain. Depending on the value of the electronic circuit board - do you spend time and money to implement a test down to the minutest level or just have a higher level report and end it there leaving the deeper maintenance to understanding the circuit or more experience faultfinding these problems ? Most sensors in automobiles are relatively simple as opposed to radio frequency equipment - example radars. The problem I see with automotive electronics is the amount of wiring and the number of connectors that are a solution looking for a failure. The one good thing is the robustness of the circuit boards. To the manufacturers credit, there are less failures with the circuit boards than there are with the sensors, harnesses and connectors. Add to that the unnecessary electronics that keep getting installed in every updated model. I'm all for electronic injection and that's where I'd stop. Everything else after that is unnecessary.
I watch at least 1 to hours of your videos ever morning. Ole dog learns new trick ever day.
I just wish we weren't all seeing tired or broken German cars people just bought that need more work than they are worth. But man a good deal is hard to pass up.
Doesn't sound right when you say it out loud.
We just had a C250 with oil and coolant leaks, along with timing codes, customer only wanted to fix the coolant leaks so it was "drivable." Became upset afterwards that the engine still made valve train noise and the check engine light was still on. I wish they would turn repairs like these away if they can't be done correctly, you're being set up to fail.
That engine sounds like an alien spacecraft when running.
with the bad car's perhaps we can donate them to the Aliens 🙂
My '84 chevy has been giving me the run-around with the starter solenoid for about a year. I finally isolated the problem to the firewall bulkhead connector.
How were you able to find the culprit?
@gigiesparza396 By connecting a heavy gauge (about 12AWG) jumper wire with ring terminal connected directly to the starter solenoid start terminal. By connecting the other end of this wire directly to the battery positive terminal, this engages the starter sonenoid. The purple conductor from the igntion switch goes through the firewall bulkhead connector. Well, engaging the ignition switch start position is supposed to apply battery current to the starter solenoid.
Mind you this problem only occurred when away from home (and tools, such as car ramps), of course!
Power (voltage) was going into the bulkhead under the dash but nothing was coming out the bulkhead into the engine harness (purple wire to starter solenoid). Thus the infuriating no-crank.
I'm starting to get the feeling some dishonest customers are going to your shop knowing very well how honest the shop is, they go in saying : "I'm wanting to get a simple starter changed/replaced"
Then the next day I complain that my head gasket was blown after you touched my car, knowing damn well it was a pre-existing condition.
I very rarely ever trust the customer
That stuff is actually kinda happening with old beater cars some customers like to drive around, I have witnessed it. Time for example: Car is over 20 years old and when there is a problem they bring it to a shop: Like let's say the blower does not work at all speeds, okay it's diagnosed as faulty blower motor resistor. Diagnosis and estimate repair cost is given to the customer, customer complains that the part/job is too expensive, when told that the price is what it is, they can find another shop to do it if they want to. Customer accepts the job..
That part gets replaced and customer is happy.
Week or two goes by, customer comes back with different problem, now the brake pedal goes to the floor. Shop says they need to inspect the vehicle, to see what the problem is. Customer agrees, they inspect it and find out how rust has eaten away a brake lines from the rear of car, fluid is slowly seeping from the rotten pipes.. Customer is told what the problem is and what needs to be done. Then the customer flips out, complains about how the car was fine until this specific shop touched it and how they ruined his car. Customer is not willing to pay for repair and repeats that It should be done "under warranty". They are not willing to get the car towed to somewhere else, instead they keep on harassing about warranty and how the shop broke their car.
you Nailed dude, 100% we had an avalanche of these morons in the past 3 Years, simply put when the Shop guys honest, humble and accommodating, they take advantage!
She just found out why the car was for sale.
The 6Million Dollar question that no one ever asks the seller is; 'Why are you selling this car? ' (if it's any good, then why not keep it?? 🤔
I'm hoping she got a good deal because the previous owner got a $5000 quote from the local dealer.
Mercedes is driven purely to show off just like people who wear Rolex or Gucci. So I really don’t feel too bad 🤣🤣🤣
great approach and awesome thought process thanks for sharing.
My experience with Mercedes, just as a DIY'er: If the battery has been weak recently and you have a ton of codes, clear all the codes, and drive it for a few days. See which ones come back. Low voltage makes all the modules 'go crazy'.
Good diagnosis. I would have put new plugs in it and coil on cylinder one also as a precaution, unknown vehicle history. I have seen similar ecu faults caused by ecu drivers overloaded by old plugs/ over worked coil packs. Have you tried Picoscope? I find there captures better and the software easier to manipulate
Daily tip.
You can’t disconnect coils on Renault engines as the coils are earthed to each other so disconnecting cylinder one (flywheel side of engine 🤷♂️) coil with un-earth cylinder 4 also makes reading codes very confusing lol
Moral of the story is pull the coil up out the cylinder don’t disconnect when looking for a bad coil.
Great video. I am now wondering if you guys offer a "used car inspection service"? You wouldn't be able to discover every little issue a car has, or potentially has, but a thorough shop as yourselves may save a customer a lot of headaches down the road.
One of the best videos ever.
Finest Fault Finding
Nice 👍🏼 !
That is a great thought process. Thank you very much
Been there. Lessons learned.
Honda turns the injector off quicker than any manufacturer I've seen. Of course cycling the ign will bring it back for testing but makes it tough when such a short period of time is given before happening again. I always wished there would be a scan tool function for disabling that protective strategy while diagnosing.
Good information
Thanks
Thanks for providing this tremendous opportunity to keep learning from your excellent videos and vast experience / knowledge .
YOU ARE A GREATEST MAN,
PLEASE DO MORE ON ELECTRIC STUFF ❤
Thank you for all you do ! I enjoy watching your videos! I would love to see one on how to set up a basic oscilloscope and use it! I know you use one in several videos but you have been doing it for years and make it look so easy! I researched for videos and not found a good one!
Excellent video 👍🏻👊🏻 keep these coming great learning experience. Thank you
Keep up the good work. I love it.
Great video as always bud. Just wondering if the coil was bad and took out the ECM. Do you think it would be wise to put a coil on it as well??
Another moral of this story is that don't buy a Mercedes (or any "premium" branded model) if you can't afford to own one as ownership of them includes the required servicing expenses people!!
Mercedes Benz + Paper Tag = "Y'all broke it when it was in here"
The windshield guy scanned my car for codes before he touched the windshield. He said he had been blamed for all sorts of problems after replacing the windshield.
These videos are the best. I gain great knowledge from them all.
Agreed ! Well said.
A coil that’s not being controlled by the ECU should be very easy to identify. Maybe a primary pattern would be more useful.
Was really looking forward to the programming part😢
Hey , buy the dc706 it will clone most of ecm tcm on market
Does it work on cummins 6.7
At what point would you check the number 1 spark plug or injector? Wondering if a spark plug could cause the grounding?
Have you been looking for factory recalls ?
I do a full scan before working on any vehicle including all the data in mode 6. Print and attach to the work order.
Do you do the same?
Might be a common problem on this engine. Had the same exact problem with a customer's car.. new Ecm fixed it.
how do you like the harborfreight box? they sent you that right? did you make a video?
Yes
People think a service is checking every nut and bolt in the car kind of thing, but if you change their wiper blades and the next day it conks out its your fault.
Check freezer frame
I put a new starter motor in a Honda accord, after a day crank sensor fault occurred. End of story bad earth brush in New starter motor caused fault
What is your definition of “new starter?” Most NEW starters are actually REBUILT by “someone, some where”
could a bad coil or plug taken out the ecm?
Bad coil can
Common issues on these M271 with the SIM271DE2.0 ECUs, the ME ignition driver gets cooked . . .
That particular ECM is KNOWN FOR LOTS OF TROUBLE and the dealer knows about it !!!!!!
1. The ECM wiring absorbs oil in parts of it.
2. The ECM fails from jump starts.
3. The ecm mosfets go bad for no reason.
4. The ecm loses programming for no reason and needs replaced.
5. The ecm can trigger false codes for no reason.
6. The ecm can hang up the transmission and cause horrible jerking or locking.
It's a dam Mercedes and let me tell you something 😂, this is THE BEGINNING OF HER NIGHTMARES.
Never had this problem with Toyotas.
if it dont crank how can it start?
I'm torn! For years Eric O "South Main Auto" has been the TH-cam champion, But you guy's are really putting pressure on his title.
Eric o is also a pretty good entertainer so personality and overall ambiance of the video is also important
engine makes a noise like power steering fluid a little low
I think that’s the mics and something they’re doing to that background noise. We are working on figuring that out with our new set up. 👍
These 2018s and newer have harness problems.
That scope gives a really poor secondary waveform. Not really usable . You’re just guessing.
Not guessing at all but what scope would you suggest.
I know a Mercedes dealership tech and he has absolutely nothing good to say about them.
uhm mercedes + 1.8L in the same sentence... come on what is this. are we back to the 80s with the 190E
I have a saying. "If I had a crystal ball 🔮 I wouldn't work here"
A new starter doesn't cause engine misfiring.
Too bad it is out of warranty by time. 8 yrs or 80K
cloning woot woot
At 0:48 with this type of vehicle assume it is nothing you did wrong.
Im a big believer in the mechanic should be talking to the customer and doing away with service writers. We can do thier job but they cannot do ours.
I hope that doesn't happen to my EV
Diesel Mercedes Benz is better. more robust as always.
Well, you don't have an ECM or coils.
Junk …not a Mercedes of yesteryears…
In my opinion you should never buy used euro trash the original owner got rid of it for a reason
The powertrains seem to be the weak part, though the unibodies and interiors seem to be pretty good. I have seen some of these types of cars in junkyards in good condition, seems like a big waste. Would be nice if people can just change out the powertrains for something simpler, like a toyota engine or something like that.