Hi, the common cause of this problem is the Park Neutral switch, also called the range switch, it is on the side ot the transmission. I will send some info on this from the factory bulletins,and a picture of the switch.
When servicing the vehicle with the VIN you entered, the following diagnosis might bhelpful if the vehicle exhibits the described symptoms.
After the installation of an NSBU switch, the PRNDL may be inoperative, read incorrect for the selected gear range, difficult to adjust or the following DTCs may be set P0708, P0847, P0872, P0875, P1711, and P1713. You may notice that the new NSBU switch was difficult to install and could not be pushed onto the selector shaft by hand. The selector shaft is mushroomed on the threaded end. Once the NSBU switch is forced over the mushroomed selector shaft the switch boss is enlarged and will not fit the selector shaft properly.
The selector shaft should be filed with a flat file to remove the mushroomed surface and new NSBU switch should be installed on the transmission using only hand pressure.
Please follow this diagnosis process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed. If these steps do not resolve the condition, please contact GM TAC for further diagnostic assistance. This diagnostic approach was developed for the vehicle with the VIN you entered and should not be automatically be used for other vehicles with similar symptoms.
#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.
Hi, here is another bulletin concerning indicator problems,it points to an ignition switch problem. These switches have been troublesome on these vehicles. I would check that out,if that doesn't solve the problem,the cluster must be your problem. You can get an exhange unit at a good price at http://www.wrwhizzard.com/.
#01-07-30-002E: MIL On, Transmission Stuck in Second or Third Gear, IPC Inoperative, DTCs P0740,P0753,P0758,P0785,P0787,P0973,P0976,P1860,P2761,P2764 and/or P2769 Set (Verify and Repair Source of Voltage Loss - (Sep 23, 2005)
This bulletin is being revised to update model years, add additional models and add additional diagnostic information. Please discard Corporate Bulletin Number 01-07-30-002D (Section 07 -- Transmission/Transaxle).
Some customers may comment on one or more of the following conditions:
Upon investigation, one or all of the diagnostic trouble codes (DTCs) P0740, P0753, P0758, P0785, P0787, P0973, P0976, P1860, P2761, P2764 and P2769 may be set depending on the vehicle.
The most likely cause of this condition may be a loss of voltage to the transmission solenoid power supply circuit.
This condition may also be the result of an incorrect installation of an aftermarket electronic device such as a remote starter or alarm system.
Important: If the vehicle is equipped with an aftermarket electronic device and the DTCs are being set when the device is being used, verify that the appropriate fuse is being supplied battery voltage during operation. If voltage is not present at this fuse, these DTCs will be set due to lack of voltage at the solenoids. This condition is most likely to occur with an incorrectly installed remote starting system. If this is the case, refer the customer to the installer of the system for corrections. ANY REPAIRS DUE TO AFTERMARKET INSTALLATION OF ACCESSORIES IS A NON-WARRANTABLE ITEM.
Hi , another problem may the ignition switch, I would check it out . These switches have a high failure rate and can cause you this problem. If you find this not to be the case,then I would believe the cluster is at fault. You can get a replacement at www.mrwhizard.com
a fair price with good service. I hope this will help you with your problem.Jerry.
The links I sent may not have worked,here it is should be good,
here are instructions for removing the cluster,if you need them.