BCM not responding.
U0140 — also written UO14O, U 0140, 0140 — is the OBD-II code for lost communication with body control module. Same code, same fix: this page covers every spelling of it.
This is the car's 'brain' for the body electronics going silent, usually because it’s drowned in a blocked drain or a wire has rotted through in a wheel arch. Huge issue on Vauxhalls and Fords in our wet climate.
U0140 is a electrical fault code, typically costing £80–£900 to put right in a UK garage.
What U0140 actually feels like to drive
- The central locking has a mind of its own—locking and unlocking while you're driving.
- Wipers suddenly stopping mid-swipe or refusing to turn off even with the key out.
- No-crank, no-start—you turn the key and absolutely nothing happens, no click, nothing.
- Dashboard lights up like a Christmas tree with 'ESP Fault', 'Power Steering Fault', and 'Brake System' warnings.
- Electric windows won't budge, usually stuck in the down position just as it starts raining.
What causes U0140?
- BCM power fault
- Water damage to BCM
- CAN wiring
UK vehicles that throw U0140 most often
- Vauxhall Corsa D/E (2006-2019) - Water ingress via scuttle.
- Ford Focus Mk3 (2011-2018) - Corrosion in the BCM/Fuse box (passenger footwell).
- Vauxhall Insignia A (2008-2017) - Wiring loom issues near the A-pillar.
- Range Rover Sport/L322 (2005-2012) - Battery drain and BCM communication drop-outs.
- Nissan Qashqai J10 (2007-2013) - Earth point corrosion causing CAN-bus silence.
- Fiat 500 (2008-present) - Fragile wiring in the tailgate loom backing up to the BCM.
How U0140 is fixed
- Test BCM power
- Dry or replace BCM
The U0140 misdiagnosis that wastes money
I’ve seen dozens of lads waste a whole Saturday throwing a new battery or a set of spark plugs at this because the car 'felt like it had a flat battery' or wouldn't crank. It’s usually a red herring. The real culprit on UK roads is almost always green crusty corrosion on the BCM pins or a chafed loom in the wing. On the Corsas, people often blame the starter motor, but it’s actually the BCM failing to send the 'go' signal because the scuttle drains are blocked and it's sitting in a puddle.
What a UK garage should charge for U0140
A simple diagnostic plug-in will run you £60 to £90 depending on where you are. If it's just a blown fuse or a loose earth, you're looking at £120 total. However, if the BCM is toasted, a new genuine unit for a Focus or Corsa is about £400-£600 plus VAT, plus another two hours' labour (£150-£200) for 'married' programming to the immobiliser. If you go the main dealer route for a Land Rover or BMW, don't be surprised to see a bill north of £1,200.
U0140 repair cost in the UK
Most U0140 repairs land between £80–£900 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 U0140
Before you let a garage quote you £800 for a new BCM, ask them to 'pin-drag' the connectors. If the pins have gone soft or corroded, the BCM might be fine, but the signal can't get through. Also, insist they check the scuttle drains under the wipers—if they’re blocked with leaves, your new module will drown just like the old one. If you do need a replacement, look into 'cloning' services; a specialist can often copy your data to a used eBay unit for £150, saving you a fortune over a brand-new blank unit from the dealer.
Can you drive with U0140?
Locks, lights, wipers may misbehave.
Urgency: medium.