1999 gmc sierra ignition module

To test the ignition module on a 1995 GMC Sierra 5.7, you can follow these steps:
1. Safety Precautions: Ensure the vehicle is in park or neutral with the parking brake engaged. Also, disconnect the negative terminal of the battery to prevent any accidental electrical shock.
2. Locate the Ignition Module: The ignition module is typically mounted on the distributor or in close proximity to it. It is a small, rectangular component with electrical connectors and heat sinks.
3. Inspect the Wiring and Connections: Examine the wiring harness and connectors leading to the ignition module. Look for any signs of damage, corrosion, or loose connections. Ensure all connections are secure and in good condition.
4. Test the Ignition Coil: The ignition module works in conjunction with the ignition coil. You can test the coil by connecting a spark tester to one of the spark plug wires and grounding the tester. Have an assistant crank the engine while you observe if a spark is present. If there is no spark, it may indicate a faulty ignition coil or module.
5. Use a Multimeter: If the ignition coil tests fine, you can use a digital multimeter to test the ignition module. Set the multimeter to the resistance (ohms) setting. Disconnect the electrical connectors from the ignition module and measure the resistance between the appropriate terminals, as specified in the vehicle's service manual. Compare the readings to the manufacturer's specifications. If the resistance values are significantly different from the specified range, the ignition module may be faulty.
6. Consult a Service Manual: It's essential to refer to a detailed service manual specific to your GMC Sierra 5.7 for accurate testing procedures and specifications. The manual will provide step-by-step instructions and values for testing the ignition module.
If you are unfamiliar or uncomfortable with performing these tests yourself, it is recommended to seek assistance from a qualified automotive technician or a GMC dealership. They will have the expertise and specialized equipment to diagnose and repair the ignition system accurately.

This might help

Depending on the actual trouble code, the problem may be the ignition module inside the distributor or the coil.

That will fix it, just be sure that when you take it out that you leave the distributor in place, they are a bear to get back in time and also be carefull not to bend one of the pins going into the distributor as you plug it back in.

There are two ECM fuses - marked ecm 1 and ecm B.
ECM B powers the fuel pump and the Veh control module which handles most of the sensors.
ECM 1 powers the ignition module, coil, injectors and the rest of the engine sensors.
You may need a repair book with diagrams to check all of the circuits for shorts.

If the crank position sensor fails then you will not get any spark,another componenet is the ICM (ignition control module)

I think the P0107 is the root cause of the problem.
P0300 is a random engine misfire on all cylinders.

Possible causes - Faulty spark plug (s)
- Faulty ignition coil (s)
- Ignition coils harness is open or shorted
- Ignition coils poor electrical connection
- Clogged or faulty fuel injectors
- Injectors harness is open or shorted
- Injectors poor electrical connection
- Improper spark plugs
- Insufficient cylinders compression
- Incorrect fuel pressure
- Intake air leak
P0107 Manifold Absolute Pressure/Barometric Pressure Circuit Low Input.
Possible causes - Manifold Absolute Pressure harness is open or shorted
- Manifold Absolute Pressure sensor poor electrical circuit connector
- Faulty Manifold Absolute Pressure sensor
- Faulty Powertrain Control Module (PCM) or Engine Control Module (ECM)

this truck uses coil on plug (distributorless) ignition. there is not distributor, therefor no cap. there is an individual coil pack for every cylinder, with a very short wire going to each plug.

Do you have power to the injectors? One of the wires to the injector will come on for a couple seconds as soon as you turn the key to the on position.The computer controls the ground side. If you do not get power to one of them start looking for an open circuit. The same power source will also go to your ignition coil and ignition module. If you do not have power on the pink wire to the coil apply a temporary fused battery power source to it and give it a try, this will also power up the injectors.
Check it out and let me know.

check for injector pulse and for compression

could be in the crank position sensor

just a thought shack