Aviloo Certified
£2M Public Liability Insured
Enhanced DBS Checked
Mobile · Pontypridd & RCT
WhatsApp PAD
PHEV battery health check

PHEVs are
complicated.

Plug-in hybrids have two batteries, weaker alternators, and habits that kill the 12V in months. One visit covers all of it. Aviloo certified high-voltage test, full 12V load test, OBD scan — £89.

73 PHEV variants · 16 brands · Mobile across Pontypridd & RCT

Book PHEV check → Check my vehicle
Three checks · one visit
The full PHEV picture
HV Aviloo testSOH % & certificate
12V load testVoltage · CCA · SOC
Full OBD scanAll modules
Service mode checksActive cell balance
Written reportEmailed same day
Issued on site · shareable instantly
Certified
Aviloo Partner
Qualified
IMI Level 1
Insured
£2M Public Liability
Vetted
Enhanced DBS
Why PHEVs are different

Two batteries.
Twice the problems.

A pure EV has one big battery. A PHEV has two — and the small one fails constantly. Any check that only looks at the high-voltage battery misses half the problem.

01 — THE 12V PROBLEM
Dies every few months
"The alternator barely runs because the engine rarely runs. The 12V never gets a proper charge cycle and fails before its time — on BMW 330e, XC60 T8, Golf GTE and most PHEVs."
→ Included in our £89 check
02 — SHRINKING EV RANGE
25 miles became 18
"PHEV high-voltage batteries are smaller and cycled harder than pure EVs. 30% degradation is common. The dashboard doesn't show it — but you feel it at the pump."
→ Aviloo measures SOH directly
03 — FAULT CODES
Cleared but not fixed
"PHEVs throw high-voltage warnings that some sellers clear before listing. The codes are gone from the dash but the history is still stored in the BMS — and we read it."
→ Full OBD scan included
What's included · £89

Everything
in one visit.

HV Battery · Aviloo

High-voltage SOH certificate

Certified SOH measurement of your traction battery — same standard as our pure EV test. Applies to all 73 supported PHEV variants.

12V Battery

Professional load test

Voltage at rest, cold cranking amps under load, state of charge. Rules out the single most common cause of PHEV "battery" complaints.

Diagnostic Scan

Full OBD across all modules

Engine, transmission, HV controller, battery management, charging system. Stored and cleared codes — sellers can't hide history from us.

Written Report

Plain English, same day

Every finding explained. What's a red flag, what's normal PHEV behaviour, what to watch. Includes the Aviloo PDF and OBD log.

On-site work
PHEV on driveway
12V battery load tester in use
OBD tool showing PHEV module list
Covered PHEV models

73 variants · 16 brands

BMW 330e, 530e, X5 45e, i8 · Volvo XC60 T8, XC90 T8, S60 T8 · Mercedes C350e, E350e, GLC 350e · VW Golf GTE, Passat GTE · Audi Q5 e-tron, A3 e-tron · Kia Niro PHEV, Sorento PHEV · Range Rover P400e, PHEV Sport · Mitsubishi Outlander PHEV · and more.

Check my vehicle →
Common questions

PHEV questions.
Straight answers.

PHEVs rely on their electric motor for most short trips, so the petrol engine — and its alternator — rarely runs. Without regular charging from a spinning alternator, the small 12V battery drifts deeper with every short trip. Two or three years later, it dies. It's not a defect — it's just how PHEVs work.
For a PHEV more than 3–4 years old, some capacity loss is normal — but 25–30% loss is on the high end. PAD's Aviloo test measures it precisely: you'll get an SOH number that tells you if the pack is within tolerance or failing prematurely.
Yes — both are £89. The PHEV test actually includes more (12V battery load test alongside the HV test), so it's better value if you're choosing between the two.
Not usually — traditional self-charging hybrids use different battery architectures that Aviloo doesn't currently support. If you drive a full hybrid (not plug-in), message us on WhatsApp with the model. We can still offer diagnostic and 12V checks, just not the HV certificate.
Yes — this is one of the highest-value pre-purchase checks. PHEVs are often sold by people who never really used the plug, so the pack can be either under-cycled (fine) or hammered (degraded). You need data, not the seller's word. See pre-purchase checks.
Book your PHEV check

PHEV battery,
12V, and full scan.
One visit. £89.

Mobile across Pontypridd and RCT. Aviloo certificate plus written PHEV report emailed same day.

Book PHEV check → Check my vehicle
Aviloo Certified
Aviloo PHEV Coverage

73 plug-in hybrid variants supported across 16 brands. Independent certified measurement.