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Note On Intermittents

Intermittent operation may be caused by a connector terminal that has not been properly crimped or seated in its connector body. Use PCM output cycling ESO2 to activate the circuits. Manipulate the wiring and connectors and observe the transmission test box indicators for malfunctions in a circuit. If electrical fault cannot be duplicated, road test vehicle using Transmission Test Box (J-38791). PCM and wiring can be by-passed by using the rotary switch to manually select gears and VCC to test transmission for intermittent operation. Incorrect 4th gear operation or excessive transaxle clutch slippage can cause an intermittent Code EO39.

Fig 1: PCM Code EO31, Schematic, Shorted MAP Sensor Circuit
G91E07541
Fig 2: Flow Chart, PCM Code EO31, Shorted MAP Sensor Circuit
GB0022529