Toyota Prius Recall R/2012/146: Short Circuit May Occur, Who Is Affected And What To Do

Urgent

How serious

3 Dec 2012

Launched

17,501

vehicles in the UK

R/2012/146

DVSA reference

Toyota recalled Prius vehicles built between 23 July 2003 and 27 March 2009. In the Hybrid system of the subject vehicles there is an electrically driven water pump assembly that circulates coolant through the hybrid components. The dealer will replace the HV electric water pump. You won't usually pay for it.¹

What’s Wrong

In the Hybrid system of the subject vehicles there is an electrically driven water pump assembly that circulates coolant through the hybrid components. It is possible the coil wire of the electric motor installed in the water pump may have been scratched during the coiling manufacturing process at the supplier. In this condition the coil wire may corrode at the scratched portion and in some cases break. If this occurs the water pump could stop working leading to illumination of various warning lights in the instrument panel. In some cases a short circuit occurs between adjacent coil wires resulting in a blown fuse for the electric power supply circuit. This will cause the hybrid system to stop while the vehicle is being driven which increases the risk of an accident.

DVSA's Original Wording

Concern: SHORT CIRCUIT MAY OCCUR Defect: In the Hybrid system of the subject vehicles there is an electrically driven water pump assembly that circulates coolant through the hybrid components. It is possible the coil wire of the electric motor installed in the water pump may have been scratched during the coiling manufacturing process at the supplier. In this condition the coil wire may corrode at the scratched portion and in some cases break. If this occurs the water pump could stop working leading to illumination of various warning lights in the instrument panel. In some cases a short circuit occurs between adjacent coil wires resulting in a blown fuse for the electric power supply circuit. This will cause the hybrid system to stop while the vehicle is being driven which increases the risk of an accident. Remedy: Replace the HV Electric Water Pump

Contains public sector information licensed under the Open Government Licence v3.0.

The Risk

If the fault occurs, the recall notice says it could lead to illumination of various warning lights in the instrument panel.

The Fix

The dealer will replace the HV electric water pump.

Are You Affected?

Prius built between 23 July 2003 and 27 March 2009 may be included. Toyota estimates 17,501 vehicles in the UK. Enter your registration to check, then confirm by VIN with Toyota, because not every car in the date range may be included.

What To Do Now

1. Check your car by registration above, then by VIN with Toyota.
2. Book with any franchised Toyota dealer, quoting the DVSA reference R/2012/146. See how to get a Toyota recall fixed.
3. Follow the letter's instructions until the repair is done. See can you drive a car with a recall?.

Related Recalls

This is one of 250 Toyota recalls in DVSA’s data. The Toyota recall launched before it was R/2012/145 on 3 Dec 2012, for loss of steering. The one launched after it was R/2013/048 on 17 Apr 2013, for passenger side airbag may fail to deploy correctly. You can also see every Toyota recall, the Toyota Prius recall history, all recalls launched in 2012 and fire risk recalls across every make.

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Source: DVSA recall R/2012/146, launched 3 December 2012. Data updated 15 October 2026. How we grade urgency.