Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2004 Saturn ION L4-2.2L VIN FFACTORY OEM SERVICE PROCEDURE
Body Control Module: Service and Repair
BODY CONTROL MODULE REPLACEMENT
REMOVAL PROCEDURE
1. Disconnect the negative battery cable.
2. Remove the front floor console.
3. Remove the wiring harness rosebud from the right center support bracket.
4. Pull back the carpet at the bottom of the right center support bracket and remove the lower nuts.
5. Remove the center support bracket nuts and remove the bracket.
6. Disconnect the small body harness connector (1) from the body control module (BCM).
7. Disconnect the large body harness connector (2) from the BCM.
8. Disconnect the small instrument panel (I/P) wiring harness connector (1) from the BCM.
9. Disconnect the large I/P wiring harness connector (2) from the BCM.
10. If equipped with Onstar, disconnect the OnStar connector.
11. Remove the BCM nuts and remove the BCM from the vehicle.
INSTALLATION PROCEDURE
1. Install the BCM to the vehicle and install the retaining nuts.
NOTE: Refer to Fastener Note in Service Precautions.
Tighten the nuts to 10 N.m (88 lb in).
2. Connect large I/P wiring harness connector (2) to the BCM.
3. Connect small I/P wiring harness connector (1) to the BCM.
4. Connect the large body wiring harness connector (2) to the BCM.
5. Connect the small body wiring harness connector (1) to the BCM.
6. If equipped with Onstar, connect the OnStar connector.
7. Pull back the carpet and position the center support bracket into position.
8. Install the center support bracket nuts.
Tighten the nuts to 10 N.m (88 lb in).
9. Install the wiring harness rosebud to the center support bracket.
10. Install the front floor console.
11. Connect the negative battery cable.
12. Program a new or a remanufactured BCM. Refer to Body Control Module (BCM) Programming/RPO Configuration. Programming and Relearning
REMOVAL PROCEDURE
1. Disconnect the negative battery cable.
2. Remove the front floor console.
3. Remove the wiring harness rosebud from the right center support bracket.
4. Pull back the carpet at the bottom of the right center support bracket and remove the lower nuts.
5. Remove the center support bracket nuts and remove the bracket.
6. Disconnect the small body harness connector (1) from the body control module (BCM).
7. Disconnect the large body harness connector (2) from the BCM.
8. Disconnect the small instrument panel (I/P) wiring harness connector (1) from the BCM.
9. Disconnect the large I/P wiring harness connector (2) from the BCM.
10. If equipped with Onstar, disconnect the OnStar connector.
11. Remove the BCM nuts and remove the BCM from the vehicle.
INSTALLATION PROCEDURE
1. Install the BCM to the vehicle and install the retaining nuts.
NOTE: Refer to Fastener Note in Service Precautions.
Tighten the nuts to 10 N.m (88 lb in).
2. Connect large I/P wiring harness connector (2) to the BCM.
3. Connect small I/P wiring harness connector (1) to the BCM.
4. Connect the large body wiring harness connector (2) to the BCM.
5. Connect the small body wiring harness connector (1) to the BCM.
6. If equipped with Onstar, connect the OnStar connector.
7. Pull back the carpet and position the center support bracket into position.
8. Install the center support bracket nuts.
Tighten the nuts to 10 N.m (88 lb in).
9. Install the wiring harness rosebud to the center support bracket.
10. Install the front floor console.
11. Connect the negative battery cable.
12. Program a new or a remanufactured BCM. Refer to Body Control Module (BCM) Programming/RPO Configuration. Programming and Relearning
Factory Service Tools
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.