1986 Jaguar Xjs — MOT failures & pass rate
The 1986 Jaguar Xjs passed 80.7% of its 806 recorded MOT tests. All cars of a similar age fail 20.4% of the time, so this is 1.0pp better than the group it competes with. Failures cluster in lighting & signalling, brakes and suspension.
What the MOT record shows
Lighting & signalling dominates the failure mix at 12.3% of all tests — 3.8 points clear of brakes, so it is the first thing to check.
At component level the recurring items are service brake performance, rbt (sp) and headlamp aim — service brake performance alone was recorded 44 times.
Mileage is the strongest signal on the record: 9.5% of 0-30k cars fail, rising to 22.7% once past 120-150k — 2.4× the risk.
Advisories point at the next bill rather than this one: suspension was flagged on 23.2% of tests without failing them.
The trend is worsening — 18.5% of tests failed in 2021 against 22.9% in 2025, the usual pattern as a fleet ages.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Lighting & signalling | 12.3% | 99 |
| 2 | Brakes | 8.4% | 68 |
| 3 | Suspension | 7.0% | 56 |
| 4 | Visibility | 6.6% | 53 |
| 5 | Emissions & environmental | 4.3% | 35 |
| 6 | Body, structure & corrosion | 3.6% | 29 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Service brake performance | 44 |
| 2 | Rbt (sp) | 42 |
| 3 | Headlamp aim | 37 |
| 4 | Washers | 35 |
| 5 | Component mounting prescribed areas | 31 |
| 6 | Headlamp | 30 |
Top advisory categories
Advisories aren't failures, but they flag work likely needed soon — useful when budgeting.
| # | Category | % of tests with advisory | Tests |
|---|---|---|---|
| 1 | Suspension | 23.2% | 187 |
| 2 | Emissions & environmental | 19.4% | 156 |
| 3 | Brakes | 11.7% | 94 |
| 4 | Body, structure & corrosion | 9.7% | 78 |
| 5 | Tyres | 9.1% | 73 |
| 6 | Lighting & signalling | 6.2% | 50 |
Failure rate by mileage
Higher-mileage cars tend to fail more — often the most useful guide to real condition.
| Mileage band | Tests | Fail rate |
|---|---|---|
| 0-30k | 42 | 9.5% |
| 30-60k | 199 | 18.6% |
| 60-90k | 249 | 18.9% |
| 90-120k | 214 | 19.2% |
| 120-150k | 75 | 22.7% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 173 | 18.5% |
| 2022 | 163 | 20.3% |
| 2023 | 171 | 18.7% |
| 2024 | 142 | 16.2% |
| 2025 | 157 | 22.9% |
What to check before buying a 1986 Xjs
On a 1986 Xjs, lighting & signalling is what the MOT record says goes wrong most — it appeared in 12.3% of tests. Check these areas before you commit.
- Lighting & signalling (12.3% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Brakes (8.4% of tests): Pads/discs are routine wear; binding, imbalance or corroded pipes are more serious — test for pulling under braking. Typical repair: £100–£350 per axle.
- Suspension (7.0% of tests): Worn drop links, bushes, springs or shocks — listen for knocks over bumps and check for uneven tyre wear. Typical repair: £150–£450 per corner.
Repair costs are rough UK ballpark ranges to set expectations, not quotes — actual prices vary widely by car, parts and garage.
Frequently asked questions
How many 1986 Jaguar Xjss pass their MOT?
80.7% of the 806 1986 Jaguar Xjs MOT tests in this dataset passed — a 19.4% fail rate.
What is the most common MOT failure on a 1986 Jaguar Xjs?
Lighting & signalling, recorded in 12.3% of tests, followed by brakes (8.4%).
Does the 1986 Xjs get worse with mileage?
Its MOT fail rate rises from 9.5% in the 0-30k band to 22.7% in the 120-150k band.
Methodology & source. Based on 806 MOT tests. Dataset: DVSA MOT testing data (2021,2022,2023,2024,2025). Data last updated 2026-07-27. Figures reflect MOT-testable defects only — read the methodology for how these are calculated and what they don't measure.