P1823 Code - Internal Mode Switch Circuit 'P' Low
Quick Answer
With the engine runtime over 5 seconds, system voltage from 8-18v, Fuel Cutoff inactive, engine torque from 30-148 ft-lb (40-200 Nm), the Powertrain Control Module (PCM) received an Internal Mode Switch (IMS) signal indicating PARK for 2 seconds, and then the IMS indicated a transitional state between Neutral and D4, conditions met for 5 seconds. Common causes include Faulty Internal Mode Switch, Internal Mode Switch harness is open or shorted, Internal Mode Switch circuit poor electrical connection. 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
- P1823 indicates Internal Mode Switch Circuit 'P' Low.
- Common causes
- Common causes include Faulty Internal Mode Switch, Internal Mode Switch harness is open or shorted, Internal Mode Switch circuit poor electrical connection.
- 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 P1823 Description
What are the Possible Causes of the DTC P1823?
- Faulty Internal Mode Switch
- Internal Mode Switch harness is open or shorted
- Internal Mode Switch circuit poor electrical connection
How to Fix the DTC P1823?
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 P1823 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.
Need more information about the P1823 code?
Need more information on how to fix the P1823 code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the P1823 code diagnosed by a professional: Find a repair shop in your area
Information for Specific Makes
- P1823 Buick — Internal Mode Switch Circuit 'P' Low
- P1823 Cadillac — Internal Mode Switch Circuit 'P' Low
- P1823 Chevrolet — Internal Mode Switch Circuit 'P' Low
- P1823 GMC — Internal Mode Switch Circuit 'P' Low
- P1823 Mitsubishi — Shift Fork Position Sensor 1 System Neutral
Frequently Asked Questions about P1823 Code
What does the OBDII code P1823 mean?
Code P1823 indicates an issue with the Internal Mode Switch Circuit, specifically that the 'P' (Park) input is reading a low signal.
What are the common symptoms of code P1823?
Symptoms may include difficulty shifting gears, the transmission being stuck in Park, or the Check Engine Light illuminating.
What causes the P1823 code?
Common causes include a faulty internal mode switch, damaged wiring or connectors in the transmission circuit, or a malfunctioning transmission control module (TCM).
Can code P1823 affect vehicle drivability?
Yes, it can cause problems such as being unable to shift out of Park, making the vehicle undriveable in some cases.
How is code P1823 diagnosed?
A mechanic will inspect the Internal Mode Switch, check the wiring and connectors for damage, and use a scan tool to monitor transmission circuit signals.
Can I fix code P1823 myself?
If you're experienced with automotive repairs, you can check for damaged wires or loose connections. However, replacing the Internal Mode Switch or diagnosing complex electrical issues may require professional assistance.
Is it safe to drive with code P1823?
Driving may not be possible if the transmission is stuck in Park, and doing so with unresolved transmission issues can lead to further damage.
How much does it cost to repair code P1823?
Repairs can range from $150 to $500 or more, depending on whether the Internal Mode Switch, wiring, or TCM needs replacement.
Can a bad battery cause code P1823?
A weak or failing battery can sometimes contribute to electrical issues, but it is not a direct cause of this code.
What tools are needed to troubleshoot code P1823?
Tools may include a scan tool capable of reading transmission-related codes, a multimeter for testing electrical circuits, and access to the vehicle’s wiring diagrams.
Discuss the causes and fixes for P1823 OBDII Code
Code P1823 comments
No comments found for this page.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.
