Asad Saeed, 33, was sacked from the Met for allegedly attacking a street drinker outside a McDonald's in Westminster but claimed later that he had been set up by a racist clique of colleagues at Belgravia police station. He accused two white PCSOs of running a "black van, white van" service for collecting them after they had finished their 12-hour shifts.
He also alleged one PCSO boasted that his family were members of the British National Party.
Mr Saeed's complaints led to an internal inquiry and the two officers resigned as they were facing disciplinary procedures for gross misconduct. It is understood that they would have been sacked.
Mr Saeed was later reinstated after an appeal but the findings against him were upheld and he has been issued with a final warning.
The Public and Commercial Services Union backed Mr Saeed's claims and repeatedly raised his concerns with senior officers. The union had concerns about one of the two PCSOs, who gave evidence against Mr Saeed even though the officer was known to have made racist comments.
Mr Saeed, who will claim a six-figure sum from the Met at an employment tribunal tomorrow, said two inspectors accused him of using the allegations of racism as a "smokescreen" to divert attention from his own alleged guilt.
Senior officers say they are privately shocked by the allegations of apartheid and say the Met's response to them was "swift and robust". Met Commissioner Sir Paul Stephenson was said to be "extremely angry" about the case.
A Met spokeswoman said: "This is an isolated case and not representative of day-to-day reality in the Met. Diversity among PCSOs is good."