Diagnostic Aids

PCM is unable to process correct engine speed data sent from PCM or intermittent or erratic RPM signal. If problem is intermittent, go to TESTING FOR INTERMITTENT AND POOR CONNECTIONS .

Fig 1: Locating Powertrain Control Module

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Fig 2: Identifying Powertrain Control Module Connectors & Terminals

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Fig 3: Identifying Underhood Fuse Block Connectors

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Fig 4: Identifying Underhood Fuse Block Connector Terminals

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