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HOMESERVICE MANUALSCHEVROLET1993SPORTVAN G30, VAN PASSENGER, 7.4 NREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 28 (ENGINE CONTROLS - TESTS W/CODES - ELECTRONIC TRANSMISSION)TROUBLE CODE CHARTSCODE 79, TRANSMISSION FLUID TEMPERATURE HIGHDIAGNOSTIC AIDS
1993 Chevrolet Sportvan G30, Van Passenger, 7.4 N

Diagnostic Aids

1993 Chevrolet Sportvan G30, Van Passenger, 7.4 NSECTION Diagnostic Aids
WARNING: This page does not describe the selected car, but rather 10 other vehicles, including the 1994 GMC Yukon, 1994 GMC Suburban, 1994 GMC Pickup, 1994 GMC Cab & Chassis, and 1994 GMC C3500 HD. However, it is still accessible from the selected car via links, so may be relevant.

Check harness routing for a potential short to ground in signal circuit. Scan tester displays transmission fluid temperature in degrees Centigrade. After transmission is running, the temperature display should rise steadily to about 100°C then stabilize. Test the transmission sensor at various temperature levels to determine if sensor is out of calibration. An out-of-calibration sensor could result in delayed shifts or TCC enabled complaint.

Fig 1: Code 79 Schematic (4L60-E Diesel) Transmission Fluid Temperature High
G94E65981
RENDER: 1.0x

NO RELATED

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Stop DIY work and contact a certified mechanic immediately if any of the following apply:

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