Ford Fiesta Mk7 1.5 TDCi 75bhp — Alternator / Smart Charge System Failure
Modern vehicles use smart charging systems to reduce engine load, but the complex regulators on the alternators frequently fail.
Severity
SevereDIY Difficulty
Moderate
Est. Cost
£250–£450
OBD Codes
P0620P0622Electrics
Typical layout and location for the Electrics assembly.
Symptoms
- Red battery warning light on dashboard
- 'Charging System Fault' message
- Systems shutting down (radio, power steering) as battery depletes
- Car fails to start
Root Cause
The internal voltage regulator or diode pack on the alternator burns out due to heat and age. Occasionally, a slipping auxiliary belt causes the issue.
How To Fix
- Test battery voltage with engine running (should be 13.8V - 14.7V).
- If below 12.5V, replace the alternator.
- Always replace the auxiliary drive belt at the same time.
- Cost: £250-450
Estimated Repair Costs
| Repair Option | Est. Cost (GBP) |
|---|---|
| DIY (parts only) | £100–£180 |
| Independent Garage | £250–£450 |
| Main Dealership | £400–£720 |
Other Faults on This Variant
DPF Blockage and Regeneration Failure
ModerateThe 1.5 TDCi diesel Fiesta is commonly used for short urban trips — exactly the wrong usage for a DPF-equipped car. Blocked DPF is the number one complaint.
EGR Valve Failure and Intake Carbonisation
ModerateEGR failure on the 1.5 TDCi Fiesta is a common companion to DPF issues. Carbon deposits block the valve and intake manifold, causing power loss and rough running.
Diesel Injector Failure and Rough Running
SevereCommon rail injectors on the 1.5 TDCi can fail, causing misfires, excessive smoke and hard starting. Injector failure can also result in diesel washing the cylinder walls, accelerating engine wear.
Disclaimer: Repair cost estimates are indicative and based on community data. Always get a quote from a qualified mechanic before proceeding with any repair.