Dual Alternator Lower Fault (Control) - P1106
The P1106 code indicates a fault in the lower alternator control circuit of a dual alternator system. This typically means the powertrain control module (PCM) has detected an issue with the voltage regulation or communication to the secondary alternator. Common causes include a faulty alternator, damaged wiring, or a failed voltage regulator. This can lead to insufficient charging, battery drain, or electrical system instability.
1. Symptoms You Will Notice
- Battery warning light illuminated
- Dimming headlights or electrical issues
- Battery not charging properly
- Engine stalling or difficulty starting
2. Most Common Causes
- Faulty lower alternator
- Damaged wiring or connectors in the alternator control circuit
- Failed voltage regulator
- PCM software or hardware issue
3. Step-by-Step Diagnosis
Step 1: Scan for additional codes and check freeze frame data.
Step 2: Inspect wiring and connectors for damage, corrosion, or loose connections.
Step 3: Test alternator output voltage and current with a multimeter.
Step 4: Check the voltage regulator and control circuit signals.
Step 5: If necessary, replace the lower alternator or repair wiring.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as the battery may not charge properly, leading to a dead battery or electrical failure.
How much does it cost to fix?▼
Repair costs typically range from $150 to $400, depending on whether the alternator needs replacement or just wiring repairs.
5. Commonly Affected Makes
This is a manufacturer-specific code. The exact manufacturer is not confirmed in our current database.