The loss-making electronics maker also lowered its forecast for DVD recorders by 13 percent and said it was considering steps to shore up that business, possibly through joint development or some other form of alliance with a rival firm.
"We need to take steps to become price competitive," Executive Vice President Tamihiko Sudo told a news conference.
Earlier on Monday, Pioneer posted a half-year net loss of 12.26 billion yen ($105.9 million), against a profit of 4.81 billion yen a year earlier.
The loss came as no surprise because Pioneer revised down its first half and full-year earnings a little over one week ago, predicting its biggest net loss on record in 2005/06 due to tumbling prices of DVD recorders and plasma TVs.
Pioneer has been unable to keep up in the flat TV and DVD recorder markets with bigger players such as Matsushita Electric Industrial Co and South Korea's Samsung Electronics Co, which leverage much larger economies of scale.
Pioneer said it had shut down two of its six production lines for plasma displays this month, including one at its Kagoshima plant in southern Japan, which it purchased from NEC Corp for close to 40 billion yen last year.
Kagoshima supplies panels to other TV makers such as Sony Corp under an original equipment manufacturer (OEM) basis and has suffered from weak demand. Sony sent shockwaves through the industry last year by saying it may stop making plasma TVs to concentrate on other types of flat TVs.
Pioneer said it now expected to ship 640,000 units of plasma displays in the year to March 2006, down from its initial projection of 800,000 units. Of that total, it cut its target for OEM shipments to 180,000 from 300,000.
Pioneer also said it had lowered its 2005/06 DVD recorder shipment target to 1.05 million units from 1.2 million units, and cut its forecast for shipments of car navigation systems in the after market by 30,000 units to 500,000.
The company has said it would unveil additional restructuring steps as early as November, beefing up a revival plan announced earlier this year that already called for 2,000 job cuts and the closure of a quarter of its plants.