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Home >> Ford >> 1996 >> F 350 2WD Pickup V8-460 7.5L >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Testing and Inspection >> Pinpoint Tests >> With EEC (OBD I System) >> Pinpoint Tests >> TB - 4X4 Low/Transmission Control Indicator Lamp >> Test Notes
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Test Notes

NOTE: You should enter this pinpoint test only when you have been directed here from diagnostic routines.

This pinpoint test is not intended to diagnose components in the transmission. To prevent the replacement of good components, be aware that the following non-EEC areas may be at fault:
- Engine performance, vacuum, or cooling
- Transmission fluid, friction elements, cooling
- Transfer case linkage
- Transfer case internal damage

This pinpoint test is intended to diagnose only the following:
- Harness circuits: 4x4 LOW, TCIL, TCS, TCSM
- Powertrain Control Module (PCM)

DESCRIPTION
- The 4x4 Low Switch is an input to the powertrain control module. When the switch is closed, it allows the use of a secondary shift schedule in low range.

- The Transmission Control Switch (TCS) allows the vehicle operator to disengage the overdrive feature when desired.

- The Transmission Control Indicator Lamp (TCIL) informs the vehicle operator of the Overdrive range status ON or OFF. The TCIL also informs the operator of certain transmission sensor/actuator malfunctions by flashing.

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