Generations
Gen1 — First Generation
2003–2008
1.8 16v, 1.9 CDTi, 2.0 DTi, 2.0 16v, 2.2 16v, 3.0 V6 CDTi
Top issues to watch for
The most serious Vauxhall Signum problems ranked by severity. We track 5 known issues — here are the ones you need to know about first.
Major
Brake hose ferrule corrosion
The brake hose ferrules (metal crimped connectors where flexible brake hoses connect to hard brake lines) suffer from accelerated corrosion on the Signum. MOT data shows this model fails at 10.6x the fleet average rate for this defect, with failures occurring from 60,000 miles onwards. The ferrules are exposed to road salt and moisture without adequate protection, leading to structural weakness that can cause brake hose separation. This affects all engine variants and represents a significant safety risk requiring immediate attention.
What happens if ignoredCorroded ferrules can separate completely causing total brake failure to that wheel or circuit. Even partial separation reduces braking efficiency and creates a dangerous safety hazard. Complete brake hose replacement is required once ferrule corrosion is identified, typically costing £150-300 per affected corner.
Independent garage
£150–£300
Specialist
£200–£350
Main dealer
£300–£500
Parts only
£40–£80
Major
Brake pipe corrosion
The steel brake pipes on the Signum suffer from accelerated corrosion, particularly where they run along the underbody and around the rear axle area. MOT data shows this model fails at 3.3x the fleet average rate for brake pipe damage and corrosion, affecting all engine variants from 60,000 miles onwards. The combination of poor corrosion protection and exposure to road salt creates multiple failure points in the brake hydraulic system.
What happens if ignoredCorroded brake pipes can burst without warning causing total brake failure. Even small leaks allow air into the hydraulic system reducing braking efficiency. Brake pipe replacement requires specialist work and system bleeding, typically costing £200-500 depending on the extent of corrosion.
Independent garage
£200–£400
Specialist
£250–£500
Main dealer
£400–£700
Parts only
£50–£150
Major
Suspension component corrosion and damage
Suspension components on the Signum suffer from excessive corrosion and structural damage, particularly affecting the 1.9-litre diesel variant. MOT data shows this model fails at 9.4x the fleet average rate for suspension component damage, with failures concentrated in higher mileage ranges from 100,000 miles onwards. The combination of the car's weight, inadequate corrosion protection on suspension arms, and exposure to road salt creates multiple failure points in the suspension geometry.
What happens if ignoredCorroded suspension components can fail catastrophically affecting vehicle control and safety. Damaged components typically require replacement rather than repair, with costs varying significantly depending on which components are affected. Multiple component replacement can cost £500-1500.
Independent garage
£300–£800
Specialist
£400–£1,200
Main dealer
£600–£1,500
Parts only
£150–£600
Minor
Exhaust system corrosion and mounting failure
The exhaust system on the Signum suffers from accelerated corrosion and mounting point failure. MOT data shows this model fails at 14.0x the fleet average rate for exhaust leaks and insecurity, with the 2.2-litre petrol variant particularly affected from 60,000 miles onwards. The combination of the car's length, low ground clearance, and inadequate corrosion protection on exhaust brackets creates multiple failure points. All engine variants are affected across higher mileage ranges.
What happens if ignoredLeaking exhaust systems fail the MOT and can allow dangerous gases into the cabin. Complete exhaust replacement is often required due to multiple corrosion points. A full system replacement typically costs £300-600 depending on the extent of corrosion.
Independent garage
£200–£500
Specialist
£250–£600
Main dealer
£400–£800
Parts only
£150–£350
1 more known issues tracked
Including wear items, electrical niggles, and generation-specific problems. Check a specific car to see which issues apply to its age and mileage.
Check a specific car →MOT failure hotspots
Based on DVSA MOT test data. These are the items where the Vauxhall Signum fails at a significantly higher rate than the average car.
Emissions failure
Exhaust & Emissions · 80-100k miles
MOT failure rate: 21x the fleet average
Sample: 505 tests
Exhaust system damage
Bodywork · 40-60k miles
MOT failure rate: 18x the fleet average
Sample: 149 tests
Headlight fault
Lights & Electrics · 120-150k miles
MOT failure rate: 9.9x the fleet average
Sample: 127 tests
Suspension component damaged or corroded
Suspension · 150k+ miles
MOT failure rate: 9.4x the fleet average
Sample: 2,178 tests
Brake hoses perished or damaged
Brakes · 60-80k miles
MOT failure rate: 9.0x the fleet average
Sample: 738 tests
Brake pipes corroded
Brakes · 40-60k miles
MOT failure rate: 7.2x the fleet average
Sample: 149 tests
Buying a Vauxhall Signum?
Check a specific car's service history to see if it's been looked after — franchised dealer records with dates, mileage, and work done.
Check service history£6.99 · Full refund if no records found
Related
Vauxhall Signum reliability FAQs
What are the most common problems with the Vauxhall Signum?
The Vauxhall Signum has 5 known issues across 2 severity levels. The most common problems relate to Brake hose ferrule corrosion and Brake pipe corrosion.
Is the Vauxhall Signum reliable?
The Vauxhall Signum has 0 dangerous and 3 major known issues. No dangerous issues are tracked, which is a positive sign.
How much does it cost to fix Vauxhall Signum problems?
Repair costs range widely. The most significant issue (Brake hose ferrule corrosion) costs £150–£300 at an independent garage. Minor issues can be under £200. Always get a full inspection before buying.