Tach and speedometer don't work transmission won't shift , I had blew a fuse with the a trailer not being wired correctly. Checked all fuses in fuse boxs. Service light is on says speed sencor. But had no problems till the fuse blew. Is there a fusiable link someware. Shift indicator light not working but I don't no how long it has been that way.

have you looked at the plug on the side of the gearbox , it may have come loose or broken wire . or have you checked all the fuses maybe one blown.

Fuse # 20 or 21 gets power through ignition. This fuse controls PRNDL indicator, speedometer, tach, & will cause transmission to not shift gears correctly. Ours took off in 3rd gear when put in Overdrive & only ran in 3rd gear. If we tried to manually shift thru gears (auto trans), it had 1st, 3rd, reverse. No 2nd or over drive. Replaced ignition. Fixed problem. Root problem was Electric motor that engaged 4 wheel low side was bad. Every time we used 4 Low side it threw power surge through ignition & blew ignition out. Good Luck.

Pinched wire between engine and trans due to mechanic fault during installation.

Sounds like brake pedal switch

Remove it..Probably installed incorrectly . Tach is probably incorrectly wired into the distributor harness and effecting rpm voltage to the speedometer and may possibly blown the voltage regulator to the gauge in the dash.

unplug the trailer first to see if it is something in it''s wiring.
not going into OD could just be that the load is too much to handle in OD.
speedo and tach I would start by checking fuses.
sounds like the problems are all related.

http://www.fullsizechevy.com/forum/general-discussion/technical-maintenance/472951-97-k1500-no-speedo-wont-shift-abs-ses-lights.html

BJB ( aka Battery Junction Box , engine compartment fuse panel ) fuse #5 is for the trailer tow reversing lamp relay & the trailer tow running lamp relay. This is to the normally open contacts on those relays, which is the circuit to the 7 pin trailer tow adapter.
- Have you checked your 7 pin trailer tow adapter for metal left in there from a trailer plug ?
If you pull those 2 relays and replace fuse #5, does the fuse blow ? If so under what conditions ( i.e. when the headlamps are turned on, or when the truck is placed in reverse ) ?

BJB Fuse # 6 feeds the park lamp relay & the headlamp relay for the autolamp function. This could be where the lights staying on it coming from, but I would have guessed just the autolamp would have stopped working.
When the parking lamps are staying on, is this with the main headlamp switch in the auto position, or with the switch turned off.

The blinking OD light is the transmission reporting an error ( trans sensor issue or the actuator circuits have failed ).

The 1st place to check for this ( which is somewhat connected to the BJB Fuse #5 ) is the DTR ( Digital Transmission Range ) Sensor on the side of the transmission.

Could be the DTR connector is gummed up with road dirt, causing an issue. Part of the DTR is for starting ( Neutral or Park acts as a switch ) and part is the reverse ( again acting like a normal switch ) the other parts of the DTR feed information to the PCM for shift control and for 44 ( if the truck is a 4x4 ) for shift operation.

Start with the DTR on the side of the trans, unplug the connector and clean it with contact cleaner, and the check on the relays above.

Please report back your findings as a comment on this problem.

Thanks

Had same problem with my 2000 dodge stratus 2.4 liter and transmission would not shift out of 1st gear. Solution was ignition fuse under the hood was blown, one side of fuse working, replaced 10 am fuse everything works, tach, speedometer, gas gauge and transmission started back to shifting.

Had same problem. Our trailer electric wiring harness had a bare wire that shorted when it touched the meatl trailer hitch. This blew a fuse. The fuse that it blew also control the transmission lock out thus not allowing you to shift out of park. I believe it is a 15 amp fuse. Of all the spare fuses in the van there is no 15 amp available. I took the fuse for the heated mirrors and swapped it with the blown fuse. Problem fixed but no heat for the mirrors. Better that than no tranny.

95% of the time when multiple things like that happen it can be linked back to a blown fuse. Thats where i would start first because with bare wires touching or grounded out it is a good chance it blew a fuse.