Monday, October 7, 2013
How to Wire a Chevy ECM
Electronic Control Monitors are often used in older Chevrolet vehicles. Once On-Board Diagnostics became standardized in 1996, the ECM units name largely changed to Powertrain Control Module (PCM). Either way, both are your Chevys computer. The ECM routinely performs system checks and monitors sensors throughout the vehicle. While both the part itself and its function sounds complex, the wiring is not. For ease in explanation, the following steps while also mirror how to replace the ECM.
Instructions
- 1
Prop open the hood over your Chevrolets engine. Disconnect the negative battery cable from the negative terminal. Wait at least five minutes until residual power within the vehicle has drained off.
2Open your passenger side door, and then open the glove box.
3Remove the glove box. How to do this depends on the model and year of your Chevrolet vehicle. Most often, the process involves releasing retaining clips, as well as stops on both sides of the glove box. Also depending on the model, you can either let the box hang down on its hinges, or you will have to remove the hinges to get the box completely out of the dashboard. For most Chevys with an ECM, the computer is located behind the glove box, and the box needs to be partially or fully removed for reasons of access.
4Disconnect the wirings harness connectors from the ECM. You do not need tools for this task. The connectors look similar to an Ethernet cable, but only larger.
5Remove the bolts holding the ECM to the ECMs retaining fixture.
6Remove the old ECM and place its replacement onto the retaining fixture. Refasten the old retaining bolts.
7Wire the new ECM to your Chevy. Take both wiring harness connectors and insert them into their appropriate ports on the new ECM. The larger harness connector will attach to the ECM in the larger left slot. The smaller Harness connector will attach to the smaller slot on the right.
Thursday, September 19, 2013
How to Remove ECM Modules on GM Cars
In General Motors vehicles, an ECM is an Electronic Control Module. It is a vehicles computer system. An apt metaphor would be that the ECM is the vehicles "brain." Among many functions, the ECM is responsible for a GM vehicles diagnostic system. An ECM module is located in the same place for most GM vehicles. It can be found behind the glove box. ECM modules are no longer used. Once the second generation of On-Board Diagnostics become standard in 1996, the module became more technologically complex and is now referred to as a PCM, or Powertrain Control Module.
Instructions
- 1
Prop the GM vehicles hood open. Remove the negative battery cable from the batterys negative terminal. Wait at least five minutes. You will need the power completely off. Once the negative cable is disconnected from the battery, you will still need to wait. There will be residual power remaining in the vehicle that needs die off.
2Remove the GM vehicles glove box. The process for this will differ by make and model year. For the most part, you will need to disengage some retaining clips, as well as some stops along the side of the box. You may need to remove some screws, especially if the box features exterior hinges connecting its door to the dashboard.
3Remove the retaining bolts on the ECM itself. The number of bolts may also vary by vehicle. The bolts can be removed with a socket wrench.
4Pull the ECM forward from retainer where it was mounted. Exercise care in doing so, since the electrical components are still attached to the module.
5Disconnect the wiring. This should most be cromprised of the ECMs two harness connectors. It will be fully disengaged at this point.
6Remove the ECM completely.