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A secondary air supply system
Operating principle At cold start (coolant temperature +15 ... +35 ?� C) of the secondary air supply system for 65 with supplies for air vent valves. Due to this, the exhaust gas enriched with oxygen, there is a secondary afterburning and thus reduces warm-up phase of the catalyst. The control is performed by the control unit Motronic J220 through the secondary air pump relay J299 to the secondary air inlet valve N112, (relief valve), and the combination valve. In addition to that after each start of the engine (when the engine temperature to 85 ?� C) of the secondary air supply system is activated with a delay of about 20 seconds to 5 seconds at idle and self-testing system.
Secondary air pump relay J299
NOTE Secondary air pump relay J2991 is inserted into the slot A4. If the removal of the relay or the control units of the relay requires an auxiliary tool, you must first disconnect the ground cable from the battery. |
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