Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
These codes are transmission codes than can affect driveability.
P0700- TCM sends codes to PCM to recognize trans problems
P1711- This is a torque converter leak down code which requires teat down & removal of front pump for inspection/repair.
P0846- These circuits shorted to ground or voltage could cause your driveability problem.the repair is usually in the pressure switch manifold or valve body.
The pressure switch manifold (PSM) is a multiple-switch assembly made up of three normally open (N/O) and one normally closed (N/C) pressure switches. The D pressure switch monitors D shift valve positioning and relays it to the transmission control module (TCM). When D pressure switch is in the open state, D shift valve should be in the unstroked position.
so what would you recommend i do next?
is there a way to check the psm sensor at the manefold to see if it could be faulty. instead of just buying one to see if it does or doesnt work.
if the truck where to turn off at a hi speed (due to the faulty sensor or intermittin open circuts) then turned back on in nutrual then put into drive. would it cause the transmission to kick out fluid externally, maybe causing the leak down code to be set off?
The tools to test this sensor properly are not in the repair field.the proper diagnosir is to check all circuits going to the sensor.Before you do anything take alook at this GM bulliten.
#02-07-30-011C: 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) - (Jun 21, 2004)
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).
Some customers may comment on one or more of the following conditions.
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.
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.
Important: The Transmission Control Module (TCM) and or the Pressure Switch Manifold (PSM) should NOT be replaced unless properly diagnosed. They are probably not the cause of the concern. It is often assumed the module is the cause of the concern when, in fact, it is another component or the wiring between the components that causes the concern.
Important: Remember, everything starts with a properly operating Neutral Start Back Up (NSBU) switch. The NSBU switch has been incorporated into what is now called the Park Neutral Position (PNP) switch. If the PNP switch does not provide the proper voltage signal to the module indicating the transmission is in either Park or Neutral, the module will not allow the starter operation. After the engine is started, and the shift lever is moved to either Reverse or one of the drive positions, the range selected portion of the PNP switch portion provides a voltage input to the module as to what range the driver has manually selected for transmission operation. The module then controls pressures, shift points and other transmission functions based on the voltage input received from the range portion of the PNP switch.
The technician may find one or more of the following conditions. The list of these conditions does not imply any type of frequency or order. They are random events and may occur in any order.
A blank PRNDL display may indicate a condition with the PNP switch and/or one or more of the four signal circuits from the PNP to the TCM.
Or, a blank PRNDL display may also occur if an out of line condition exists with the Serial Data Circuit (CKT 2470, yellow wire) from the TCM to Splice Pack 205.
If the Gear Selected display does not match the shifter position in the vehicle, diagnose using one of the following methods.
The PNP switch, as referenced in SI, is known as the NSBU switch in the Parts information. It is now serviced with a Park Neutral Position Switch Kit, P/N 29540479.
A flashing PRNDL display may be the result of incorrect sensor inputs or transmission abuse protection modes being received by the TCM. The following are some of these conditions:
Transmission abuse protection modes are encountered when a customer performs one of the following types of maneuvers:
When the TCM encounters any one of the above conditions, the TCM will flash the PRNDL and default the transmission to Neutral. A flashing PRNDL indicates something is/was incorrect. The transmission may need the attention of a qualified service technician.
Important: If the old PNP switch will not slide from the selector shaft without the effort, the selector shaft may need to be filed to remove flaring on the end of the selector shaft. This is important, installing the new switch onto a selector shaft that has damage will cause damage to the new PNP switch.
Important: If the new PNP switch will not slide onto the selector shaft easily, the selector shaft may need to be filed to remove flaring on the end of the selector shaft. This is important, installing the new switch onto a selector shaft that has damage will cause damage to the new PNP switch.
Tighten Tighten the bolts to 27 N·m (20 lb ft).
Important: Installation of the front shield and rear shields are important. Without proper installation of the shield, a return repair is probable. Follow all directions as listed on the installation instructions sheet included in the Switch kit, P/N 29540479.
Tighten. Tighten the nut to 24 N·m (18 lb ft).
Important: Clear all DTCs before returning the vehicle to the customer.
Switch kit, Park Neutral Position
Parts are currently available from GMSPO.