Diagnostics & Mystery ProblemsDiagnostic helpCommunity Starter

2024 Mercedes-Benz C-Class — check-engine light turned itself off — still scan it?

CanyonSellerCommunity StarterJul 3, 20262024 Mercedes-Benz C-Class C300Portland
The light was on for two days and then disappeared before I could schedule service. Car feels normal. Is there still likely to be useful stored or pending data if I scan it now? I would rather test this logically than replace parts.
permalink

Related listings

25 replies

OldSchoolTunerCommunity StarterCommunity StarterJul 3, 2026permalink
Intermittent stuff lies if you only catch it once. Get a real battery/charging test on the 2024 Mercedes-Benz C-Class, not just resting voltage, before blaming a module. Don't erase codes until someone who can help has seen them. On “benz c-class — check-engine light turned itself,” that was the fork that mattered for me. Keep sale price, fees, and rate as three different conversations. Climate here is different, so treat that as a local data point. I'll poke at it this weekend.
BoxerShopper534Community StarterCommunity StarterJul 3, 2026permalink
If it were in my driveway, a pressure test beats staring at a dry driveway if the 2024 Mercedes-Benz C-Class is losing coolant with no puddle. Save the big job until that test fails. Have you gotten a second quote in writing? If the story changes I'll post the new data.
ShopMiles248Community StarterCommunity StarterJul 3, 2026permalink
If it were in my driveway, move a coil or plug on the 2024 Mercedes-Benz C-Class if it's cylinder-specific and see whether the code follows. Don't erase codes until someone who can help has seen them. That's the sequence I'd use. I'd rather be boring and correct. Video is ugly but it shows the hesitation.
CityMom597Community StarterCommunity StarterJul 3, 2026permalink
If it were in my driveway, write temp, speed, and in-gear vs coast when the 2024 Mercedes-Benz C-Class does it — then decide on parts. Don't erase codes until someone who can help has seen them. If they can't show the line item, I assume it's hiding. Video is ugly but it shows the hesitation.
OldSchoolTunerCommunity StarterCommunity StarterJul 3, 2026permalink
I wouldn't throw parts yet. Swap the cheap/easy piece first on the 2024 Mercedes-Benz C-Class and see if the fault moves. If the cheap test changes it, stop and reassess. This is from a 2024 Mercedes-Benz C-Class in Portland. Write the result down so the next test isn't a repeat of the last one. If the story changes I'll post the new data.
QuietLearner245Community StarterCommunity StarterJul 3, 2026permalink
Ask what changed right before it started. If a shop can't duplicate it on the 2024 Mercedes-Benz C-Class, bring a video plus freeze-frame data, not just a story. If the cheap test changes it, stop and reassess. This is from a 2024 Mercedes-Benz C-Class in Portland. When does it actually happen? Doing the boring step first on purpose.
ApexEnthusiastCommunity StarterCommunity StarterJul 3, 2026permalink
Ask what changed right before it started. Capture voltage while the 2024 Mercedes-Benz C-Class is actually failing — after it restarts you've lost the clue. That's the branch I'd chase this week. Any freeze-frame data saved? A day of patience here is cheaper than a wrong part. Happens in gear, not in park, for what that's worth.
DetailScout4Community StarterCommunity StarterJul 3, 2026permalink
I'd want a measurement, not a hunch. Move a coil or plug on the 2024 Mercedes-Benz C-Class if it's cylinder-specific and see whether the code follows. You'll know quickly if you're on the wrong tree. I'd want a dollar figure or a measured spec, not 'should be fine.' Not trying to scare you — just skip the expensive first guess. Only after sitting overnight so far.
BoxerShopper534Community StarterCommunity StarterJul 3, 2026permalink
Intermittent stuff lies if you only catch it once. Loaded-suspension checks on the 2024 Mercedes-Benz C-Class catch play that a wheels-hanging inspection misses. Save the big job until that test fails. On “benz c-class — check-engine light turned itself,” that was the fork that mattered for me. Was this after sitting overnight? Next check is the cheap one I can do in a driveway.
CamberGarage964Community StarterCommunity StarterJul 3, 2026permalink
Intermittent stuff lies if you only catch it once. Move a coil or plug on the 2024 Mercedes-Benz C-Class if it's cylinder-specific and see whether the code follows. You'll know quickly if you're on the wrong tree. On “benz c-class — check-engine light turned itself,” that was the fork that mattered for me. This is from a 2024 Mercedes-Benz C-Class in Portland. Have you gotten a second quote in writing? If your situation is the opposite, ignore me. I'll update if anything new shows up.
ApexEnthusiastCommunity StarterCommunity StarterJul 3, 2026permalink
I wouldn't throw parts yet. Swap the cheap/easy piece first on the 2024 Mercedes-Benz C-Class and see if the fault moves. Save the big job until that test fails. This is from a 2024 Mercedes-Benz C-Class in Portland. Any freeze-frame data saved? If it repeats twice more I'll book time.
NewCarTuner625Community StarterCommunity StarterJul 3, 2026permalink
I wouldn't throw parts yet. Two 2024 Mercedes-Benz C-Classs can feel identical and have different causes, so measure before you copy someone else's repair. Don't erase codes until someone who can help has seen them. Verbal 'we'll take care of it' is not a plan. I keep a notes app thread for this now.
TowWeekend964Community StarterCommunity StarterJul 3, 2026permalink
I'd want a measurement, not a hunch. Loaded-suspension checks on the 2024 Mercedes-Benz C-Class catch play that a wheels-hanging inspection misses. Save the big job until that test fails. This is from a 2024 Mercedes-Benz C-Class in Portland. If you share a photo of the worksheet, easier to sanity-check. Not interested in a five-hour wait for a shrug.
ManualDaily690Community StarterCommunity StarterJul 3, 2026permalink
Log the conditions before you spend. Write temp, speed, and in-gear vs coast when the 2024 Mercedes-Benz C-Class does it — then decide on parts. That's the branch I'd chase this week. On “benz c-class — check-engine light turned itself,” that was the fork that mattered for me. Do that first. Climate here is different, so treat that as a local data point. Not interested in a five-hour wait for a shrug.
SunBeltGarage401Community StarterCommunity StarterJul 4, 2026permalink
That's a good start, but I wouldn't stop there. Loaded-suspension checks on the 2024 Mercedes-Benz C-Class catch play that a wheels-hanging inspection misses. Don't erase codes until someone who can help has seen them. Just my two cents from doing this recently. Not driving it hard until I know more.
SunBeltGarage401Community StarterCommunity StarterJul 3, 2026permalink
I'd want a measurement, not a hunch. Get a real battery/charging test on the 2024 Mercedes-Benz C-Class, not just resting voltage, before blaming a module. Save the big job until that test fails. Take it or leave it — that's what I'd do. No warning lights, which is why I'm documenting it.
QuietLearner245Community StarterCommunity StarterJul 4, 2026permalink
This is usually cheaper to test than to guess. Get a real battery/charging test on the 2024 Mercedes-Benz C-Class, not just resting voltage, before blaming a module. That's the branch I'd chase this week. Have you gotten a second quote in writing? Make the next action something you can finish this week. If the story changes I'll post the new data.
DailyGeek732Community StarterCommunity StarterJul 4, 2026permalink
This is usually cheaper to test than to guess. Swap the cheap/easy piece first on the 2024 Mercedes-Benz C-Class and see if the fault moves. If the cheap test changes it, stop and reassess. Learned this the expensive way on a previous car. Might be overthinking it, but I'd rather overthink than overspend.
BoxerShopper534Community StarterCommunity StarterJul 4, 2026permalink
Log the conditions before you spend. Capture voltage while the 2024 Mercedes-Benz C-Class is actually failing — after it restarts you've lost the clue. That's the branch I'd chase this week. On “benz c-class — check-engine light turned itself,” that was the fork that mattered for me. Did the worksheet show tax yet? I'd rather pay for diagnosis than a second guess-repair.
CamberGarage964Community StarterCommunity StarterJul 4, 2026permalink
Log the conditions before you spend. Capture voltage while the 2024 Mercedes-Benz C-Class is actually failing — after it restarts you've lost the clue. Save the big job until that test fails. On “benz c-class — check-engine light turned itself,” that was the fork that mattered for me. Was this after sitting overnight? I'm in no rush to be a hero on it.
DetailScout4Community StarterCommunity StarterJul 4, 2026permalink
Log the conditions before you spend. If a shop can't duplicate it on the 2024 Mercedes-Benz C-Class, bring a video plus freeze-frame data, not just a story. If the cheap test changes it, stop and reassess. On “benz c-class — check-engine light turned itself,” that was the fork that mattered for me. I'd want a dollar figure or a measured spec, not 'should be fine.' Only after sitting overnight so far.
OldSchoolTunerCommunity StarterCommunity StarterJul 4, 2026permalink
Fair point. Counterpoint: Swap the cheap/easy piece first on the 2024 Mercedes-Benz C-Class and see if the fault moves. You'll know quickly if you're on the wrong tree. This is from a 2024 Mercedes-Benz C-Class in Portland. Write the result down so the next test isn't a repeat of the last one. Trying not to diagnose from the couch.
ShopMiles248Community StarterCommunity StarterJul 4, 2026permalink
Start with the test that can prove you wrong. Move a coil or plug on the 2024 Mercedes-Benz C-Class if it's cylinder-specific and see whether the code follows. Save the big job until that test fails. This is from a 2024 Mercedes-Benz C-Class in Portland. No need to make it theatrical. Happens in gear, not in park, for what that's worth.
CanyonSellerCommunity StarterCommunity StarterJul 4, 2026permalink
OP update: scanned the 2024 Mercedes-Benz C-Class again and still only have the one pending code, no new lights. If this is nothing, great. I want that in data.
CanyonSellerCommunity StarterCommunity StarterJul 4, 2026permalink
OP update: scanned the 2024 Mercedes-Benz C-Class again and still only have the one pending code, no new lights. Video is ugly but it shows the hesitation.
Sign in to reply

Similar discussions