Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there is a problem with the car's check engine light system. The car's computer can't control the light properly.
The P1690 code indicates an issue with the electrical circuit that controls the Malfunction Indicator Lamp (MIL), commonly known as the check engine light.
The P1690 code is triggered when the Engine Control Module (ECM) detects a fault in the electrical circuit responsible for controlling the MIL. This could be due to a short circuit, open circuit, or poor connection in the wiring or connectors associated with the MIL.
• Check engine light not illuminating
• Check engine light always on
• No noticeable performance issues
• Faulty MIL bulb or LED
• Damaged or corroded wiring/connectors
• Faulty Engine Control Module (ECM)
MIL: Malfunction Indicator Lamp, also known as the check engine light.
ECM: Engine Control Module, the computer that controls engine functions.
• Inspect the MIL bulb or LED for damage.
• Check wiring and connectors for corrosion or damage.
• Test the ECM for faults.
• Replace the MIL bulb or LED if faulty.
• Repair or replace damaged wiring/connectors.
• Replace the ECM if necessary.
• Multimeter
• OBD-II scanner
• Screwdriver set
$100 - $500
Moderate
• Dodge Ram
• Jeep Grand Cherokee
• Chrysler Town & Country
• Regularly inspect wiring and connectors.
• Ensure the ECM is properly maintained.
• Check the MIL bulb or LED periodically.
Electrical Circuit Issue
• Have a professional inspect the vehicle.
• Do not ignore the check engine light.
Check your vehicle's warranty for coverage on electrical components.
This code has been commonly associated with electrical issues in older vehicle models with traditional bulb-based MIL systems.
Moderate – While the vehicle may operate normally, the inability to display MIL warnings could mask other serious issues.
Driving with a malfunctioning MIL may prevent timely detection of other critical engine issues.
• Engine running
• Use of OBD-II scanner
The MIL is located on the vehicle's dashboard, typically integrated within the instrument cluster.
Q: Can I drive with a P1690 code?
A: Yes, but it's important to fix it soon to ensure the check engine light can alert you to other issues.
Q: Will a P1690 code affect vehicle performance?
A: No, it typically doesn't affect performance but prevents the MIL from indicating other problems.
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