K 3500 Truck 4WD V8-6.6L DSL Turbo VIN 1 (2001)
Transmission Position Switch/Sensor: All Technical Service Bulletins
A/T - Slow/No Gear Engagement/Engine No Start
Bulletin No.: 02-07-30-011C
Date: June 21, 2004
TECHNICAL
Subject:
Slow or No Engagement of Automatic Transmission, No Start, Blank PRNDL Display, Flashing PRNDL, DTC P0708, P0872, P0847, P0875, P1711,
P1713 or U1000 Set (Diagnose Condition, Repair According to Procedure)
Models:
2001-2004 Chevrolet Silverado
2001-2004 GMC Sierra
with Allison(R) LCT1000 Automatic Transmission (RPO M74) and
6.6L Duramax(TM) Diesel Engine (RPO LB7) or 8.1L Gas Engine (RPO L18)
Supercede:
This bulletin is being revised to add model years and additional model information and add graphics. Please discard Corporate Bulletin Number
02-07-30-011B (Section 07 - Transmission/Transaxle).
Condition
Some customers may comment on one or more of the following conditions.
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The PRNDL display is flashing.
^
The engine will not start.
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The "Service Engine Soon" Indicator lamp is illuminated.
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The transmission does not shift properly.
^
The vehicle will not move, transmission will not engage.
Cause
Moisture contamination within the Park Neutral Position (PNP) Switch may cause this condition. This is sometimes referred to as the Neutral Start
Back-up (NSBU) Switch. On a left turn, water spray from the left front tire is directed directly at this switch. Proper installation of the "Front Shield" and
"Rear Shield" are essential for proper repairs.
Technician Diagnosis
This bulletin ONLY applies to vehicles equipped with a two connector PNP switch as shown above.
A complete and through diagnosis must be performed by a qualified electrical technician to determine the cause and avoid needless replacement of good
components.
