508 Start-Stop Error P1A9C

Hello everyone, my car hasn't been using the ECO (start-stop) feature for a while. But since I live in a small town, I didn't think it was a big deal. Anyway, last week, as soon as I turned on the ignition, the "Engine failure: Have vehicle repaired" warning appeared on the display. The speedometer read "SERVICE." I cranked it, it started, and the engine warning light wasn't on. Only the "SERVICE" warning remained. I didn't notice any problems with the car's operation. There weren't any strange noises. However, whenever I got in and reconnected the car, the "Engine failure: Have vehicle repaired" warning came right back. I took it to my mechanic, who said it might be the battery. I had the battery tested by an electrician. It was giving a very low voltage when I cranked it. He said it needed to be replaced. I replaced it. As car owners know, there's something like an electronic circuit on the battery. That's why, without seeing the brand and model of the battery, I found the battery suitable for my vehicle from Varta's website (https://www.tr.varta-automotive.com/tr-tr/battery-finder). I bought the N70 12V 70ah EFB battery. The old battery turned out to be a Varta E39 AGM. (This is my first time changing the battery; I've owned the vehicle since 2020.) The battery was installed, but the error continued. My electrician said there might be a problem with the circuit on it. He checked the electricity with a test pen and there was electricity coming to each of them. But he said I couldn't understand it. He got the error code P1A9C in his software. Now, when I turn the ignition, it still says engine failure: have the vehicle repaired. And the ECO is not engaging. I finally went back to my mechanic, and he recommended Simge Mehmet in Ostım. Has anyone had their vehicle repaired by this mechanic or encountered a similar problem? Sometimes I wish they had never added a start-stop eco mode to this car. edit: I didn't write the exact model of the car: Peugeot 508 2012 1.6 HDi 112hp berhanb2024-11-08 16:13:15

Hello, first of all, I wish you a speed improvement. I experienced the same problem (P1A9C) in my own car last winter. There is a start-stop capacitor under the left front fender. It is a bit costly. If you don't replace it, it will cause serious damage to the transmission. When you press the brakes in the morning, it will make strange noises before you even start the car.

Sir, I am having the exact same problem. I changed the battery and installed the AGM but I still have the same problem.

Hello, I have the same problem, were you able to solve it?