IGNORING one small but important warning light on your car’s dashboard could end up costing you a staggering £4,000 in repairs, experts have warned.
While many motorists brush off the odd symbol or flashing light, this one could cause serious damage to your car’s gearbox if left unchecked.
Drivers are being urged to pay close attention to the Transmission Temperature Warning Light – a little-known icon that could mean the difference between a smooth drive and a massive repair bill.
A study by Warrantywise found that two thirds of British drivers don’t recognise half of the warning lights that appear on their dashboards.
With dozens of symbols flashing on modern dashboards — from seatbelt alerts to engine warnings — many drivers struggle to tell which ones demand urgent attention.
But according to Jonathan Such, Motoring Expert at vehicle finance provider First Response Finance, this particular light is one of the most important to know about.
Jonathan explains: “This warning light, often shown as a gear with a thermometer inside, indicates that your transmission fluid is overheating.
“It’s not one most people recognise but ignoring it can lead to serious and expensive damage.”
Transmission fluid is essential to protect your gearbox from heat and friction.
Once it gets too hot, transmission fluid loses its ability to protect key components — increasing friction, damaging parts, and potentially causing complete gearbox failure.
“Gearbox replacements are among the most expensive repairs a driver can face, with costs typically ranging from £800 to £4,000*, depending on the make and model of the vehicle,” Jonathan warned.
You’re most likely to see this warning light during demanding conditions — such as towing, climbing steep roads, or idling in traffic on a hot day.
If it comes on, drivers are advised to pull over safely, switch off the engine and let the car cool down before driving any further.
“Don’t try to ‘push through’ or get to your destination,” Jonathan advises.
“Even a few extra miles can be the difference between a quick fix and a major repair.”
To prevent expensive repairs, drivers should ensure their vehicle is serviced regularly, maintain proper transmission fluid levels, and steer clear of harsh driving that can overload the gearbox.
Jonathan added: “Your dashboard is there to protect you. If in doubt, check your manual or speak to a mechanic. It could save you thousands.”
Experts also warn that another commonly ignored dashboard icon – the oil warning light – can lead to catastrophic engine damage if not dealt with immediately.
If it lights up, you should stop as soon as possible.
Continuing to drive could cause severe engine wear or complete failure.
Once the car has cooled down, check the oil level and top up if needed.
However, if oil levels appear normal, the car should not be driven further.
Instead, it’s best to have it transported to a garage for a full inspection.
Ultimately, while most dashboard lights might seem harmless at first glance, ignoring the wrong.
Three warning lights that could cost you big
1. Engine Management Light – Potential Loss: £500
This light can indicate anything from a loose fuel cap to major engine issues. A red light signals a serious problem, while amber suggests something less severe but still needs fixing. Ignoring this could slash £500 off your trade-in value.
2. ABS Light – Potential Loss: £500
Crucial for your car’s safety, a lit ABS light is a red flag for buyers. Even a minor sensor fault can trigger it, but not fixing it could lead to a £500 reduction in your car’s value.
3. Service Light – Potential Loss: £200
This light reminds you that a service is due. Neglecting it could knock £200 off your car’s worth. Regular servicing is key, especially if your car is under warranty.
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