99 tahoe tranny question

[10ga]

first off i have a 99 tahoe, 5.7, 4x4, 4 door with 184,000 mile and the only thing that i've had to replace was the fuel pump at 125,000. the other day i parked on a hill, put the parking brake on, put it in park, turned it off and got out for about 30 minutes. when i started to take off it was having a hard time getting up the hill, like it was in 2nd or 3rd gear. the service engine light was on and i manuelly pulled it down to first, well it took off then with no problems. also the light that shows you what gear you're in was also out. i was only about a mile from home so i drove it home, parked it, and just forgot about it. the next morning i started it up and everything was normal again and has been for the last 2 weeks. do you think this is a sign of problems to come? or was it just something minor? i know it has a lot miles on it but i'm just not ready to trade it or i really don't want to get into some expensive repairs because of it's value. thanks for any help.

[Jeremy-WI]

Sounds like an ignition switch problem, you should be able to find more details by searching the chevy part of this website, the technical service bulletin has been posted a few times

[MT-2500]

If it does it again have the codes read and get the code no and post back.
That is why they put them check eng lights on there.
It is trying to tell you to check it out.
MT

[horse482]

Here is the TSB
TSB# 01-07-30-002D

Malfunction Indicator Lamp On, Transmission Stuck in Second or Third Gear, Instrument Cluster Inoperative.

04-05 Rainier
99-00 Escalade
02-05 Escalade and EXT
03-05 ESV
97-99 Chevy/GMC Full Size; Pickup, Suburban, Tahoe (Yukon) (Old Style)
97-05 Blazer (Jimmy), (Bravada), Corvette, Express (Savana), S10 (Sanoma)
99-05 Silverado (Serria) (New Style)
00-05 Suburban, Tahoe, Yukon, Yukon XL
02-05 Avalanche, Trailblazer, EXT, Envoy, XL, XUV
04-05 Colorado/ Canyon
03-05 H2
04-05 GTO
With 4L60-E, 4L65-E, 4L80-E or 4L85-E

Condition: One or more of the following problems:
- The Malfunction Indicator Lamp is on.
- The transmission is defaulted to second gear (4L80/85-E).
- The transmission is defaulted to third gear (4L60/65-E).
- The instrument cluster is inoperative.

Possible DTC’s: P0720, P0753, P0758, P0785, P0787, P0973, P0976, P1860, P2761, P2764, and P2769 may be set depending on the vehicle.

Cause: The most likely cause of this condition may be a loss of voltage to the transmission on circuit 1020. This loss of power may be caused by an open in the ignition switch. This condition my also be the result of an incorrect installation of an aftermarket electronic device such as a remote starter or alarm system.

Correction: With the ignition switch in the RUN position, test for battery voltage at the appropriate fuse listed below.
97 S/T Trans 24
98-05 S/T Cluster 11
02-05 S/T Ignition 0
97-00 C/K(Old) Trans 20
99-05 C/K(New) Ignition 0
97-02 G-Van Trans 20
03-05 G, H-Van Ignition 0
03-05 H2 Ignition 0
04-05 GTO Auto Trans
97-04 Corvette Enging 1
05 Corvette ACC/TCM
04-05 Colorado/Canyon Trans

If the battery voltage is present at the fuse, inspect the ignition voltage circuit between the fuse and the transmission for possible opens. If the battery voltage is not present at the fuse, replace the ignition switch.

If the vehicle is equipped with an aftermarket electronic device and the DTC’s are being set when the device is being used, verify that the appropriate fuse listed above is being supplied battery voltage during operation. If voltage is not present at this fuse, these DTC’s 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 they system for corrections.

[Jeremy-WI]

My question is why doesn't the TSB list every vehicle these trannys are used in? Some of the symptoms are the same except pre-OBD2 vehicles will have different codes, some vehicles lose the PRNDL and others have a cable on them.

What are DTC's P2761, P2764, and P2769? What years/models are they on? I guess the part I don't understand is the P2xxx part, I know P0xxx is obd2 generic, P1xxx is manufacturer specific, and Px7xx is transmission related