How to reprogram my 98 chevy tahoes electronic control module

The transfer case control module on a 1998 Chevy Tahoe 4x4 is typically located under the driver's side of the dash, near the steering column. To remove it, you will need to first locate the module and then disconnect the electrical connectors. Then you will need to remove any mounting bolts or screws that are holding the module in place. Once those are removed, you should be able to gently pull the module out. It may be helpful to consult your vehicle's service manual for specific instructions and diagrams to locate and remove the module. It is also recommended to get it check by a professional mechanic, as the problem might be other than the module itself.

No such thing on an electronically controlled transmission. This uses shift solenoids, not modulator valves.

New transmissions do not have a modulator valve. They are electronically controlled.

Could be your Body Control Module (BCM) has gone bonkers. GM geniuses decided their vehicles needed more computers on board. Most of your dash and interior switches and controls are routed through the BCM, a small mini-computer. Later models require reprogramming of these modules to the main computer. Not sure about your '97, you better check. Lights, wipers, turns-they all go to the BCM, before the wires go to the actual motors or bulbs. Not friendly territory for DIY'ers.

Who told you that one ? Module ignition modulator 2003 Chevy Tahoe ! No such thing! Your best bet would be to take your vehicle to a qualified repair shop .
The electronic ignition (EI) system is responsible for producing and controlling a high energy secondary spark. This spark is used to ignite the compressed air/fuel mixture at precisely the correct time. This provides optimal performance, fuel economy, and control of exhaust emissions. This ignition system consists of a separate ignition coil connected to each spark plug by a short secondary wire. The driver modules within each coil assembly are commanded ON/OFF by the powertrain control module (PCM). The PCM primarily uses engine speed and position information from the crankshaft and camshaft position (CMP) sensors to control the sequence, dwell, and timing of the spark.

The fuel pump control module is controlled by the ECM - engine control module , Possibility of DTC'S stored ! You need to take to Chevy Dealer !
The engine control module (ECM) supplies voltage to the fuel pump control module (FPCM) when the ECM detects that the ignition is ON. The voltage from the ECM to the FPCM remains active for 2 seconds, unless the engine is in Crank or Run. While this voltage is being received, the FPCM closes the ground switch of the fuel pump and also supplies a varying voltage to the fuel tank pump module in order to maintain the desired fuel rail pressure.

It can be done if you have the proper equipment, the correct software to install and the knowledge. Its really not needed most of the time many companies sell remaned BCM.s or will fix yours if they don't have one in stock. Check out Cardone:

http://www.cardone.com/products/electronics/electronics-products-remanufactured/body-control-modules

Body control module part of the computerized items of the truck along with the ECM (electronic control module)

Check that the heater core's two tubes that enter the firewall are getting hot. If they are, then you are having a blend door problem which will require disassembling the dashboard instruments to get at the vacuum motors that control the blend doors.

If the heater core is not getting hot at both tubes, then the following procedure outlines how to change the heater core out:

Removal & Installation






Heater core removal






To Remove:

1. Remove the HVAC assembly.
   
2. Remove the heater core cover screws.
   
3. Remove the heater core cover from the HVAC assembly.
   
4. Remove the heater core gasket from the core.
   
5. Remove the heater core from the HVAC module assembly.

To Install:

1. Install the heater core to the HVAC module assembly.
   
2. Install the heater core cowl gasket to the HVAC module assembly.
   
3. Install the heater core cover and screws to the HVAC module assembly.
   
4. Install the HVAC module assembly to the vehicle.

Here it is straight from Alldata:

1. Ground pin G of the Data Link Connector (DLC).**Bottom left pin**

• Receiver will respond by locking, and unlocking doors within 2 seconds.

1. Press any button of the first transmitter to be programmed.
2. The control module will respond by locking/unlocking doors and activating rear window release.
3. Press any button of the second transmitter to be programmed (if used).
4. The control module will respond by locking/unlocking doors and activating the rear window release.

1. Remove the ground applied to the reprogrammed connector.

1. Transmitter operation is verified locking and unlocking the doors and activating the rear window release