Vauxhall Astra Astra J 1.6 CDTi 110bhp — 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
Timing Chain Rattle and Tensioner Failure
CriticalThe 1.6 CDTi A16DTH/DTJ engine is notorious for timing chain noise and failure, often from as low as 60,000 miles. This is the most serious known fault on the Astra J diesel.
Clutch Pedal Sticking Down
SevereThe clutch pedal fails to return to the top of its travel, often getting stuck halfway or hitting the floor completely.
DPF Blockage and Regeneration System Failure
SevereDPF blockage is extremely common on the Astra J 1.6 CDTi. The engine's tendency to get stuck in failed regen cycles results in diesel contaminating the engine oil — a serious secondary issue.
Disclaimer: Repair cost estimates are indicative and based on community data. Always get a quote from a qualified mechanic before proceeding with any repair.