When a customer brought in his 2016 Ford Transit Custom camper, he was at his wit’s end. The dashboard kept going blank — speedometer, warning lights, and even the odometer display all cut out at random times. He’d already replaced the cluster with a donor unit, but the problem came straight back.

A local garage had tried their best and then turned to us at Dudley Auto Service in Luton for a proper diagnosis. That’s exactly what we do best — finding the real cause before replacing parts unnecessarily.

Step 1: Gathering Information

Our technicians always start by collecting as much detail as possible. The owner had bought the camper already converted and had only replaced the auxiliary battery once after leaving the fridge on. He also noticed that the fault usually appeared after a longer drive or when taking a right-hand bend.

That clue was valuable — it hinted at a wiring or connection issue that showed up under body flex.

Step 2: Verifying the Fault

We scanned the entire vehicle — the Transit had 12 electronic modules in total. Several showed communication errors. We cleared the codes and went for a long test drive. Nothing at first — typical intermittent issue!

So we used the van for a few days, driving it in normal conditions. Eventually, the fault reappeared, and we noted that three modules — the instrument cluster (IPC), audio control module (ACM), and front display (FCDIM) — all dropped offline together.

This told us the fault was most likely in the i-CAN communication network.

Step 3: Digging Deeper

We used our oscilloscope to monitor the i-CAN network from the OBD port. No irregularities appeared even when the dashboard failed, so we switched to testing the mid-speed CAN network.

This time, we saw clear voltage drops pulling the signal to ground — a classic sign of wiring damage.

Armed with Ford factory wiring diagrams, we traced the fault to connector C300, hidden behind the dashboard on the left A-pillar. It wasn’t easy to reach, but once we separated it, the cluster stayed alive and communication returned.

We reconnected the circuits in stages until we could isolate the fault — a damaged section of wiring in the camper conversion, where the interior fitters had added equipment.

Step 4: Repair and Result

After repairing the damaged section and reassembling the dashboard, the van was back to perfect working order. The customer was relieved — and surprised that the problem wasn’t the dashboard after all.

It’s another reminder that diagnosis matters more than guesswork. A new part can’t fix a wiring issue, but the right testing can.

What This Story Shows

We handle complex electrical diagnostics for all makes and models — not just Ford. Whether it’s a Volkswagen, Mercedes-Benz, BMW, or Vauxhall, our diagnostic approach is the same: methodical, accurate, and transparent.

If you’re having recurring electrical faults or dashboard issues, book a diagnostic appointment online or learn more about our diagnostic services .

We’re also trusted for routine servicing, MOT testing, and DPF cleaning — all carried out to main dealer standards.

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