Transmission will not shift out of low on my chevy 2001 3500 , the code is p0700 and p1781, p1721

Question edited for clarity.
Question moved to model category.

All the codes are generic and can be Googled. That is a very sick car!

Chevy Cobalt P0411: Secondary Air Injection System ... - 700R4

https://www.700r4transmissionhq.com > p0411-chevy-...
Apr 16, 2019 - P0411 is a general OBDII trouble code, which means that it has the same meaning for the Chevy Cobalt as it would any other car or truck.

The P0974 code is generic powertrain code related to the transmission, including pressure faults and sensor failures. In this case, the engine control module (ECM) has detected a fault with a high voltage reading from the shift solenoid A control circuit.

P0974 OBD-II Trouble Code: Shift Solenoid A Control Circuit ...

2010 Chevy Cobalt P0751 P0752 Shift solenoid stuck on/off

https://www.obd-codes.com > forums > viewtopic
Feb 12, 2018 · 5 posts · 2 authors
The solenoids are located on the valve body, inside the transmission. Inside the tranny, check the red wire (from underhood fuse block) for ...

The P2430 error will be set if the PCM finds improper voltage or resistance in the secondary air injection system air flow/pressure sensor circuit bank 1 and the check engine light will blink.

Solution of OBD Code Error P2430 - PartsAvatar.ca

What is a P0700 Code? The P0700 code indicates that there's a malfunction with your vehicle's Transmission Control Module (TCM). This computer monitors your transmission and works with the Powertrain Control Module (PCM) and Engine Control Module (ECM) to shift gears when necessary.

P0700 Code: What It Means and How to Fix It

What the P0365 code means. Essentially, the P0365 code means that there has been a lack of voltage detected from the camshaft position sensor B in bank 1 by the PCM within a few seconds of the engine starting.

P0365 OBD-II Trouble Code: Camshaft Position Sensor B ...

P0171 - OBD-II Trouble Code Fuel System Too Lean (Bank 1)

https://repairpal.com > obd-ii-code-p0171
Mar 13, 2017 - When the P0171 code sets, the oxygen sensors are detecting too little oxygen in the exhaust (running "lean") and the control module is adding more fuel than ...

Well, unless you want to get into rebuilding your transmission, I would recommend a filter change and adding Lucas Transmission Fix. I have seen that combo fix many troublesome transmissions. Other than that, you still could have a sticky valve in the valve body or even a worn/broken band or clutch. Basically, the TCM is telling you that it commanded a gear change and it didn't see evidence of that gear change happening hence the limp mode. If the Lucas didn't fix it, and it was my car, i would get a Power Torque transmission from Oreilley's with a 3 year unlimited mile warranty, install that an be done with it- get back to enjoying the car.

First and last code are transmission related and the middle one is EGR. Is the transmission acting up?

p1781 is manufacturer control transmission, p0731 is gear 1 ratio incorrect, p1784 is manufacturer control transmission, p0700 is trans, control system malfunction. all of these codes refer to tranny.This code normally points to a faulty transmission control module, but this is an expensive part and you should have an experienced Dodge technician diagnose the problem first. or a transmission specialist. the other codes are probably associated with the p0700 code. have a good day !

The transmission control module (TCM) uses the controller area network (CAN) to signal the engine control module (ECM) that the TCM is requesting malfunction indicator lamp (MIL) illumination. This happens when the TCM has determined that a failure that affects emissions has occurred in the transmission control system. When the ECM receives the correct message from the TCM, DTC P0700 will set.
Circuit Description
The engine coolant temperature (ECT) sensor is a variable resistor, that measures the temperature of the engine coolant. The ECT sensor has a signal circuit and a low reference circuit. The engine control module (ECM) supplies 5 volts to the ECT signal circuit, and a ground for the ECT low reference circuit. When the ECT is cold, the sensor resistance is high. When the ECT increases, the sensor resistance decreases. With high sensor resistance, the ECM detects a high voltage on the ECT signal circuit. With lower sensor resistance, the ECM detects a lower voltage on the ECT signal circuit. If the ECM detects an excessively high ECT signal voltage, which is a low temperature indication, DTC P0118 sets.

Diagnostic Aids
• If a short to a separate 5-volt source occurs this DTC may set.
• Use the Temperature vs Resistance table to test the ECT sensor at various temperature levels to evaluate the possibility of a skewed sensor. A skewed sensor could result in poor driveability concerns

Sounds like you need a new coolant temp. sensor , but test it ! Videos on youtube showing how to do it .
Circuit Description
To improve shift feel, the transmission control module (TCM) may request that the engine control module (ECM) reduce engine torque during shift events. When such a request is received, the ECM responds by retarding the base ignition timing and notifying the TCM that the request has succeeded. If the ECM is unable to comply with the request, the ECM sends the TCM a message that the request has failed.
The torque reduction request is sent to the ECM through a communication network called the controller area network (CAN). Two circuits are used to communicate CAN data between the ECM and TCM. A fault in the CAN will not cause DTC P1781 to set by itself. If a CAN fault occurs, other DTCs will set before DTC P1781.
When the TCM receives a torque reduction failure message from the ECM, then DTC P1781 will set. DTC P1781 is a type A DTC.

I use a site that deals with nothing but codes for automobiles, and this is what they gave me for your year, make and model of your car. PO128 is Electrical System failure. P1781 is Engine Torque Signal Circuit, and PO700 is Engine and Cooling. If you gave me the right codes, this is the answer Chevy gave me. hope this helps

From what I can find in my book - they are (generic code)
P 0700 Transmission Control System Malfunction
P 0133 O2 Sensor Circuit Slow Response (Bank 1 Sensor 1)
P 0137 O2 Sensor Cicuit Low Voltage (Bank 1 Sensor 2)
P 0131 O2 Sensor Circuit Low Voltage (Bank 1 Sensor)
P 0171 System Too Lean (Bank 1)
Could not find these codes in the GM section - that is why I went with the Generic codes

There are a couple of bulletins from GM on valves causing these codes. # 05-06-01-030D and #PIP3063C are the bulletin #'s you need to have them look at. They are related to the valves in the cylinder head causing your exact symptoms. You should contact another dealer or GM customer assistance with this info. Good Luck

there is a Technical service bulletin for this problem, the number of the TSB is 01575, TSB Date:January 1, 2004
It has to do with engine valve seating problems.

The Transmission shop lacks the skills and tools need to do the job. It's best to call around for a shop that has a proper scanner to talk to the TCM computer. The real trouble codes are in there. The best place would be a shop that has a ASE mechanic on duty or the Dealership.

Here what the two codes means:

P0700 Transmission Control System Malfunction
It means you have a trans control problem in the trans computer.
You will need to get it on a trans capable scanner to see what the trans code or problem is.

the P1781 is set during engine start up when the ECM & TCM do not communicate properly during initial power up. It will only illuminate the service light if the condition occurs in 2 consecutive start cycles, but the DTC will be stored in the failure records after the first cycle.