P1634 Code - Ignition 1 Power Circuit Low Voltage
Quick Answer
With the key on, no Class 2 serial data received, the Powertrain Control Module (PCM) detected an improper Ignition 1 Power Circuit (Circuit 1) voltage. Common causes include Faulty Ignition Control Module (ICM), Faulty Ignition 1 Power, Ignition 1 Power harness is open or shorted. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P1634 indicates Ignition 1 Power Circuit Low Voltage.
- Common causes
- Common causes include Faulty Ignition Control Module (ICM), Faulty Ignition 1 Power, Ignition 1 Power harness is open or shorted.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code P1634 Description
What are the Possible Causes of the DTC P1634?
- Faulty Ignition Control Module (ICM)
- Faulty Ignition 1 Power
- Ignition 1 Power harness is open or shorted
- Ignition 1 Power circuit poor electrical connection
How to Fix the DTC P1634?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P1634 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Information for Specific Makes
- P1634 Audi — Accelerator Pedal Position Sensor 2 Signal High Input
- P1634 Buick — Ignition 1 Power Circuit Low Voltage
- P1634 Cadillac — Ignition 1 Power Circuit Low Voltage
- P1634 Chevrolet — Ignition 1 Power Circuit Low Voltage
- P1634 Chrysler — TCM Internal Watchdog Performance
- P1634 Dodge — TCM Internal Watchdog Performance
- P1634 Ford — Data Output Link Circuit Failure
- P1634 GMC — Ignition 1 Power Circuit Low Voltage
- P1634 Hyundai — Cruise Control Lamp Malfunction
- P1634 Jeep — TCM Internal Watchdog Performance
- P1634 KIA — Generator Terminal Open Circuit
- P1634 Mazda — Generator Terminal Open Circuit
- P1634 RAM — TCM Internal Watchdog Performance
- P1634 Volkswagen — Accelerator Pedal Position Sensor 2 Signal High Input
Frequently Asked Questions about P1634 Code
1. What are the common symptoms of OBDII code P1634 (Ignition 1 Power Circuit Low Voltage)?
The common symptoms of P1634 include difficulty starting the vehicle, reduced engine performance, and illuminated warning lights on the dashboard.
2. What are the possible causes of OBDII code P1634?
Potential causes of P1634 can include a faulty ignition switch, damaged wiring or connectors in the ignition circuit, a weakened battery, or a malfunctioning powertrain control module (PCM).
3. How can I diagnose the underlying issue causing OBDII code P1634?
Diagnosing P1634 typically involves checking the condition of the battery, inspecting the ignition switch and related wiring, testing the PCM, and using a multimeter to measure voltage in the ignition circuit.
4. Can a weak battery trigger OBDII code P1634?
Yes, a weak or failing battery can lead to a drop in voltage in the ignition circuit, triggering code P1634. It is recommended to test the battery's condition and replace if necessary.
5. Is it safe to continue driving with OBDII code P1634 present?
It is not advisable to continue driving with code P1634 active, as it can affect the vehicle's performance and lead to potential starting issues. It is recommended to address the underlying problem promptly.
6. How can I repair OBDII code P1634 at home?
If you are comfortable with automotive repairs, you can attempt to fix P1634 by checking and replacing damaged wiring, connectors, or the ignition switch. However, complex issues may require professional assistance.
7. Will resetting the fault codes make OBDII code P1634 disappear?
Resetting the fault codes may temporarily clear OBDII code P1634, but if the underlying issue is not addressed, the code is likely to reappear once the problem is detected again by the vehicle's system.
8. Can extreme weather conditions cause OBDII code P1634 to trigger?
Extreme weather conditions, especially cold temperatures, can sometimes affect the performance of the battery and lead to a drop in voltage in the ignition circuit, potentially triggering code P1634.
9. What role does the powertrain control module (PCM) play in OBDII code P1634?
The PCM monitors the voltage in the ignition circuit and can trigger code P1634 if it detects a low voltage condition. A malfunctioning PCM can also be a potential cause of this fault code.
10. How much does it typically cost to repair OBDII code P1634 at a professional auto repair shop?
The cost of repairing P1634 can vary depending on the underlying issue, parts needed for replacement, and labor costs. It is recommended to contact a local auto repair shop for a more accurate estimate based on your specific situation.
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