Mercedes Adblue Fault
Drive a Mercedes C Class? If so, you’ll be familiar with the unique charm and sophistication these luxury vehicles offer. However, like any other car, your Mercedes requires regular servicing to keep it running like new.
Recently, a client brought their Mercedes C220 to our garage in Langport with an engine management light issue.
An engine management light is never a welcome sight.
To make matters worse, the client’s Mercedes also had an AdBlue warning light. Talk about a nightmare situation.
Thankfully, they’d heard good things about our garage from a friend and decided to bring their vehicle to our Mercedes experts to be fixed.
What We Found
Once our Mercedes specialists had the client’s vehicle, they immediately began a thorough investigation to diagnose the problem.
At Shires Garage, we’re committed to helping you get the most out of your vehicle. That’s why we always conduct a detailed examination to identify the root cause of any issue your vehicle is facing.
As your local independent Mercedes specialist, we use a comprehensive 15-step diagnostic process to accurately pinpoint and fix problems during your first visit.
We always provide you with a quality, first-time fix, no matter the problem.
Upon further inspection, we discovered that the client had recently topped up the AdBlue in their C220 but had accidentally overfilled it. This is fairly common, as not many people know that overfilling the AdBlue system can lead to further damage.
Initially, a thorough visual inspection of the vehicle’s engine didn’t reveal any clear issues, so we proceeded to check for any fault codes.
The Diagnostic Evaluation
After scanning the client’s C220, our experts found a fault code we present:
- P140300 – AdBlue control unit malfunction.
Armed with this information, our Mercedes specialists turned their attention to the AdBlue pump and began examining the wiring. It became clear that no power was reaching the AdBlue module, prompting our team to strip back the wiring for a closer look.
Our specialists found that the main wiring loom was completely worn, leading to severe corrosion of the power wire. This could be the reason why the client’s vehicle was showing warning lights on the dashboard.
Our technicians also discovered an issue with the AdBlue level sensor during this process. The client had previously mentioned that they had accidentally overfilled the system.
Typically, this shouldn’t be possible as the system relies on ultrasonic sensors to detect the fluid level accurately. However, an overfilled AdBlue system can cause these sensors to malfunction, leading to incorrect readings and miscommunication throughout the vehicle.
Before we solved the issues, we called the client to discuss our findings.
At Shires Garage, we always keep you in the loop. We only start working on your vehicle once you’ve given us the green light. You remain in complete control of the situation from start to finish.
Once we had the green light from the client, we proceeded with the fix.
Fixing The Mercedes C220 EML
To fix the AdBlue wiring loom problem, our experts sourced a genuine Mercedes-branded replacement. We then replaced the damaged wiring and re-insulated it on-site to ensure a proper and lasting repair.
As your local independent Mercedes specialist, we always use Mercedes-branded or high-quality aftermarket parts on your vehicle. This ensures you receive the quality needed for optimal performance.
Once this issue was solved, we drained the AdBlue tank and refilled it to the correct level to ensure there were no further problems present.
With the AdBlue system properly calibrated, we took the Mercedes for a road test. The Engine Management Warning light was no longer displayed, confirming that the vehicle was back to its optimal driving condition.
You Can Rely on Shires Garage
After reassembling the AdBlue system and completing the road test, our Mercedes specialists performed a final inspection of the C220 to ensure everything was in perfect working order.
Our client’s car was returned to them within 24 hours, faster than the main dealerships could offer. Plus, our services gave the client better value for money.
Thanks to our thorough approach at Shires Garage, we achieved a first-time fix, sparing the client from the hassle of repeat visits and additional repairs.
When you combine the fast turnaround time, better-than-dealership value, and our dedication to honesty and transparency, it’s no wonder the client was pleased.
Our client left the garage with their Mercedes C220 in peak working condition, with no more EML or AdBlue warning lights on their dashboard.
Need help with your Mercedes? Call Shires Garage today and let our experts provide you with a quality, first-time fix.
