Greetings everyone, I figured I'd create a topic, keep it up-to-date, and ask if anyone has experienced this particular problem before while I arrange for the car to be taken in for servicing.
The problem is:
After locking and leaving the car for more than a few minutes, the first try to start the engine fails. To turn off the power supply, I have to press the start button twice; then, it starts (perfectly) on the second try. On the road, the stop/start works as it should, and turning off the engine will start it normally as long as I don't get out and lock the car. However, no matter how many times I try to start the car after locking it, it always refuses on the first try. There is no crank, and no mechanical noise either. It's as if there's something necessary to fire the engine, like a code from the key, that it only receives after I cycle it. (The easiest way to describe the problem is that I have to click the start button three times to start the automobile.)
It used to be an occasional occurrence that I attributed to not pressing the brake pedal firmly enough or holding the button down for long enough, but now it's a feature of the car. I haven't checked, but the voltages appear fine on the command screen at 14.7-14.9v (though that might be different when the alternator isn't working), so I'm wondering if it needs a new battery.
Despite my best efforts, I was unable to locate any information that addressed this particular issue with my model.
Issue with starting the C238 350D 4matic coupe
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Gorrillaas
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Since someone else could be experiencing the same problem and find this information helpful, I will update the thread.
I took my car in to Harrogate MB on Tuesday. They found a short on Circuit 87 (the ignition switch relay), but instead of replacing it, they decided to clear the fault and give it back to me. Guess what? The problem is still there. I'll have to bring it back in 10 days.
The no crank start failure occurs about two minutes after the car is locked, so something the car does puts it into a situation where circuit 87 can't reply without receiving the request twice; I've been going over all the possible beginning scenarios and have zoomed in on this.
My only hope is that it's only a matter of installing a new relay.
I took my car in to Harrogate MB on Tuesday. They found a short on Circuit 87 (the ignition switch relay), but instead of replacing it, they decided to clear the fault and give it back to me. Guess what? The problem is still there. I'll have to bring it back in 10 days.
The no crank start failure occurs about two minutes after the car is locked, so something the car does puts it into a situation where circuit 87 can't reply without receiving the request twice; I've been going over all the possible beginning scenarios and have zoomed in on this.
My only hope is that it's only a matter of installing a new relay.
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Gorrillaas
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Car was dropped of at the dealer this morning, they have ruled out a defective relay for circuit 87 and tested the battery, they are getting 13v on start up when it has to be 13.5v therefore the no crank start failure, they are now looking at the wiring for the issue, this is going to be pricy I guess.
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RuthHimmic
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Curiously, the voltage tolerance is significantly wider than 13V and 13.5V, so I don't understand why they brought it up. Consequently, it wouldn't produce a no start issue. Ours may start with a voltage of as little as 11.5V in the battery.
Does the vehicle have or had an immobilizer? We occasionally encounter a similar issue with ours, which is why I am inquiring about the ghost immobilizer.
Does the vehicle have or had an immobilizer? We occasionally encounter a similar issue with ours, which is why I am inquiring about the ghost immobilizer.
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Gorrillaas
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They brought up the topic of a ghost/immobiliser, but I don't have the answers because the automobile is brand new to me (I got it in June) and is eight years old. What I do know is that the problem has manifested itself since then, starting as an impulsive event that has now become permanent. (but it may have been lying around before the purchase, unresolved, ready to manifest itself in the way it did)
From what I gathered from that statement—ignoring the actual voltage quoted—it seems like the car isn't delivering the voltage needed to start the engine once it has fully shut down. However, it's worth noting that SAs often exaggerate or forget what the tech told them, so their claims can be misleading.
Strangely, after that setback, it functions just fine, regardless of what it needs from a "cold" (cold doesn't mean temperature) start.
From what I gathered from that statement—ignoring the actual voltage quoted—it seems like the car isn't delivering the voltage needed to start the engine once it has fully shut down. However, it's worth noting that SAs often exaggerate or forget what the tech told them, so their claims can be misleading.
Strangely, after that setback, it functions just fine, regardless of what it needs from a "cold" (cold doesn't mean temperature) start.