BMW F30 320d – Power Failure, Electrical issues and Maintenance

[Clint@MMS AUTO]

"Lets call this Part 1"

Had an F30 320d come in — but not in the usual way. It arrived on the back of a tow truck, with the driver reporting that the car had suddenly lost power and shut down completely.
🔧 Once it was here, I put the battery on charge and got the car into the workshop. First step was diagnostics, and almost every module/controller had faults. While troubleshooting, I monitored the voltage and saw it drop to under 10V, confirming that the alternator had failed.

🛠️ Alternator Out, Refreshed & Reinstalled
We removed the faulty alternator and discussed options with the owner. He specifically requested we have it reconditioned instead of replacing it with a new one — budget-conscious and fair for a workhorse vehicle.
So we sent the unit off to a trusted local specialist for a rebuild. While waiting for the alternator to return, the owner also asked me to do a little cosmetic upgrade — swapping out the chrome kidney grilles for a set of gloss black ones he had lying around.

✅ Back in Action
When the reconditioned alternator came back, it looked great and functioned even better. I reinstalled it, verified everything was installed correctly, and with the battery fully charged, the system voltage held strong at idle and under load.
Took it out for a test drive — no more low voltage warnings, no battery drain, and no fault codes on return. Everything was functioning perfectly again.

The driver collected the car later that day and was off to fetch his next Uber customer — this time with full electrical health and a fresh new look up front.

Thanks for reading.

 

[Clint@MMS AUTO]

BMW F30 320d – Uber Workhorse in for Inspection & Fault Finding (Part 2)

About a month had passed and then I received a call from the owner. He mentioned that one of the cars would be coming in for a few electrical issues – namely a rear left brake light not working, front left fog light out, and a concern that the battery was run flat.
Apparently, the Uber driver had been charging multiple devices with the car off, and assumed the lighting issues were electrical faults caused by an electrical fault.

🔍 Initial Observations:
When the car arrived, I moved it into the workshop and immediately picked up that it was overdue for a service. These Uber cars clock crazy mileage – easily 5,000km a month, so it’s no surprise. But the driver hadn’t reported this to the owner. I made a note to flag it with him.

🔧 Brake Light & Fog Light:

• Started off with the rear left brake light – checked both the bulb and holder.
  • The bulb was burnt out and the terminal had some minor corrosion.
  • I didn’t have stock on the specific bulb type, so I made a note to order a full box. These cars are used hard and regularly — best to keep spares on hand for the next inevitable one.
• Moved on to the front left fog light:
  • Stripped out the wheel arch lining and found the bulb had fallen out and was just chilling inside the lower tray.
  • Clearly a previous install job done elsewhere. Secured the bulb properly and used a cable tie to make sure it’s not going anywhere. Gave it a light tug — all good now.

🔌 Diagnostics & Battery Drama:
While I was scanning the car with the diagnostic tool, I noticed the battery voltage dropped quickly — had to connect the battery charger to complete the scan.

• A whopping 68 fault codes were stored!
• The driver admitted to jump-starting the vehicle multiple times due to the dead battery — likely related to the excessive power drain from charging phones.

✅ Findings & Plan:
I reported everything back to the owner:

• Engine service is overdue.
• Battery needs replacing & coding/registration.
• Brake light bulb to be replaced at the time of service.

We’ve scheduled the car to return in 2 days once the new battery has been installed. I’ll handle the Minor oil service, bulb replacement, and register the new battery when it’s back.

 

[Clint@MMS AUTO]

BMW F30 320d – Uber Workhorse In For Minor Service, Battery Registration & Touch-ups (Part 3)

Following up on Part 2 of this visit — the new battery had been installed, and the car returned to us so we could take care of the remaining items on the to-do list.
This round included:

• A minor oil service (the last major was done in Feb),
• Replacing the rear brake light bulb,
• Running diagnostics to clear stored fault codes,
• Registering the new battery, and
• Installing a set of front bumper splitters the owner had lying around.

🔧 Minor Oil Service (4,600km Overdue)
First thing I noticed when I opened the bonnet was just how dirty the engine bay was — typical for a car that sees Uber-level daily use. Before starting anything, we blew out the dust using compressed air.
Then added Motul Engine Flush, let the engine idle for the required time, and got the car onto the lift. Drained the old, dirty oil, and while that was draining, we took the opportunity to install the new front splitters. (No pics of this unfortunately, but they came out neat.)
Once the oil was fully drained, we replaced the drain plug washer, refitted the drain plug, and moved on to the oil filter. We gave the oil filter housing and cap a clean, then installed a new oil filter and O-ring, topped up with Motul X-Clean 5W40, and gave the engine bay a good wipe-down and detail — because even Uber workhorses deserve to look clean under the bonnet.

💡 Other Items Done:

• ✅ Replaced the rear brake light bulb (from Part 1).
• ✅ Cleared all 68 stored fault codes using diagnostics.
• ✅ Reset the oil service reminder in the CBS menu.
• ✅ Registered the new battery to the car’s system.

With all that sorted, the driver collected the car and headed off to pick up his next customer — now with a clean bill of health and no annoying warnings on the dash.

Another round of maintenance done right, keeping the Uber's on the road and earning.