McLaren has announced it has ended its running for the day with three hours remaining of day three at Jerez.
Fernando Alonso was able to take to the track at 0900 after progress was made with the new Honda power unit late on Monday afternoon, and the MP4-30 quickly completed 32 laps after managing just 12 on the first two days combined.
However, Alonso was confined to the garage at lunchtime after noticing a problem during an out lap and McLaren confirmed via Twitter that a loss of cooling water pressure had proved a major enough issue to curtail its running on Tuesday.
Jenson Button will take over the car on the final day of testing at Jerez before a gap of two weeks between the first and second tests.
We've had a loss of cooling water pressure & have removed the power unit for inspection. That’s a long process, so it ends today's running.
— McLaren (@McLarenF1) February 3, 2015
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