Starter relay circuit fault.
P0615 — also written PO615, P 0615, 0615 — is the OBD-II code for starter relay circuit. Same code, same fix: this page covers every spelling of it.
This is basically the car's brain telling you it tried to flick the 'on' switch for the starter motor, but nobody answered the phone. Often crops up on Fords and Vauxhalls when the relay gets tired or the wiring gets salty.
P0615 is a electrical fault code, typically costing £50–£250 to put right in a UK garage.
What P0615 actually feels like to drive
- Turning the key or hitting the 'Start' button results in a single click or total silence.
- The car starts perfectly fine from cold but refuses to turn over once you've popped into the shops (heat soak).
- Intermittent 'Starting System Fault' message on the dash (common on Fords and Vauxhalls).
- The car 'kangaroos' or the dash lights flicker briefly when you try to crank it.
- Sometimes it takes four or five turns of the key before the engine finally decides to fire up.
What causes P0615?
- Relay failure
- Wiring
UK vehicles that throw P0615 most often
- Ford Focus Mk3 1.6 TDCi (2011-2015)
- Vauxhall Astra J / Insignia A (A20DTH engines) 2009-2017
- Land Rover Discovery 3/4 (TDV6) - notorious for relay corrosion
- Nissan Qashqai J11 1.5 dCi (2014-2018)
- Fiat 500 1.2 Petrol (2008-2020) - often Earth strap issues
- Renault Clio Mk4 (2012-2019)
How P0615 is fixed
- Relay replacement
The P0615 misdiagnosis that wastes money
I see folks throwing new batteries and £150 starters at this constantly before they've even checked a fuse. They assume because the key turns and nothing happens, the motor's dead. In reality, it's often just a corroded pin in the under-bonnet fuse box (UEC) or a broken wire tucked inside the loom where it rubs against the gearbox casing. I've lost count of how many 'dead' starters were actually just a £15 Bosch relay or a bit of green crusty wiring needing a solder.
What a UK garage should charge for P0615
For a basic relay swap, you're looking at £15-£30 for a quality Bosch or Hella part, plus maybe 30 mins labour (£40-£60). If I'm chasing a broken wire in the loom, expect a £70-£90 diagnostic fee first. A main dealer will easily double these prices, charging £150/hr just to plug the tool in. If it turns out to be a fried BCM (the body computer), you're looking at £400+ for a refurbished unit.
P0615 repair cost in the UK
Most P0615 repairs land between £50–£250 including parts and labour. The spread is wide because the cheap fix (a sensor, a hose, a leak) and the expensive fix (a major component) throw the same code — which is why a proper diagnosis before parts are bought saves the most money.
Bob's tip on P0615
Before you let a garage swap your starter motor, ask them: 'Have you done a voltage drop test on the trigger wire?' If they look at you blankly, move on. A proper tech should be able to bridge the relay pins to see if the motor turns over manually. If the motor spins when bridged but won't start with the key, your starter is fine and the fault is in the control side—likely the BCM or the relay itself. Don't pay for a £300 starter job when a £20 relay solves it.
Can you drive with P0615?
May fail to start.
Urgency: medium.