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Home >> Suzuki >> 2007 >> SX4 Base, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 241 (Engine Performance - DTC P0401 - P0507) >> DTC P0420: Catalyst System Low Efficiency >> Diagnostic Aids
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Diagnostic Aids

WARNING: This page is about a different car, the 2006 Suzuki Reno and 2006 Suzuki Forenza. However, it is still accessible from the selected car via links, so may be relevant.

The catalyst test may abort due to a change in the engine load. Do not change the engine load (i.e. A/C, coolant fan, heater motor) while a catalyst test is in progress.

An intermittent problem may be caused by a poor connection, rubbed-through wire insulation, or a wire that is broken inside the insulation.

Any circuitry, that is suspected as causing the intermittent complaint, should be thoroughly checked for the following conditions: