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TB - Testing Notes

NOTE: You should enter this Pinpoint Test only when you have been directed here from Quick Test.



REMEMBER


This Pinpoint Test is not intended to diagnose components interior to the transmission. To prevent the replacement of good components, be aware that the following non-EEC areas may be at fault.



- Engine

Performance, vacuum, cooling

- Electrical

Alternator, battery, integrity

- Transmission

Hydraulic 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, OCL, OCS

- Processor assembly

DESCRIPTION

The 4x4 low switch is an input used by the processor assembly. When the switch is closed, the processor allows use of a secondary shift schedule while in low range.

The Overdrive Cancel Switch (OCS) allows the vehicle operator to disengage overdrive when desired.