B1717 - Mirror Power Fold Control Switch Shorted Low

Introduction:

The B1717 diagnostic trouble code (DTC) indicates a fault within the power folding mirror system of a vehicle. Specifically, it signifies that the vehicle's computer has detected a short to ground in the circuit connected to the power fold control switch. This means the switch is providing an unintended electrical path to ground, preventing the power fold mirrors from functioning correctly. Addressing this issue promptly is crucial to restore the full functionality of your vehicle's mirrors and ensure safe operation.

Table: B1717 - Mirror Power Fold Control Switch Shorted Low

Detailed Explanations:

Code Definition: Mirror Power Fold Control Switch Circuit Shorted to Ground

This DTC indicates that the vehicle's computer has detected an unintended electrical path to ground within the circuit connected to the power fold control switch. This means that a wire or component in the circuit is making contact with the vehicle's metal frame or chassis, creating a short circuit. This short prevents the normal flow of electricity and can disrupt the operation of the power folding mirrors.

Symptoms

• Power fold mirrors do not function (do not fold in or out): This is the most obvious symptom. The mirrors will not respond to the power fold switch.
• Power fold mirrors fold erratically or uncontrollably: A short can cause intermittent or unpredictable operation of the mirrors.
• Other electrical issues may be present (e.g., blown fuses): A short circuit can overload the electrical system and cause fuses to blow.
• The mirror control switch might feel loose or unresponsive: This could indicate damage to the switch itself.
• The vehicle's battery may drain if the short is severe and persistent: A constant short to ground can drain the battery over time.

Possible Causes

• Short to Ground: This is the root cause identified by the DTC. It means a wire in the power fold switch circuit is making unintended contact with the vehicle's chassis or other grounded metal components. This contact creates a low-resistance path for electricity to flow directly to ground, bypassing the intended circuit components. Finding and isolating this physical contact is crucial to resolving the issue.

• Faulty Power Fold Switch: The switch itself could be internally shorted. Over time, the internal components of the switch can degrade or become damaged, leading to a short circuit. This is especially common if the switch has been exposed to moisture or physical stress.

• Damaged Wiring Harness: The wiring harness connecting the switch to the vehicle's control module is susceptible to damage. Friction, heat, and environmental factors can cause the insulation on the wires to crack or fray, exposing the conductive core and creating a short to ground if it touches metal. Rodents can also chew on the wiring.

• Corroded Connectors: Corrosion within the electrical connectors of the switch or wiring harness can create a short circuit path. Corrosion increases resistance and can also create a conductive path to ground if it bridges between terminals. Inspect connectors for green or white deposits, which are signs of corrosion.

• Water Intrusion: Water entering the switch or connectors can cause a short to ground. Water is conductive and can create an unintended electrical path, especially in the presence of contaminants like salt or dirt.

• Faulty Control Module: (Less common) While less likely, the body control module (BCM) or other module responsible for controlling the power fold mirrors may be faulty and misinterpreting the circuit's status. This is usually considered only after ruling out other potential causes.

• Aftermarket Accessories: Poorly installed aftermarket accessories can sometimes interfere with the vehicle's electrical system and cause shorts. This is especially true if the accessories tap into existing circuits without proper protection or isolation.

Troubleshooting Steps

• Visual Inspection: Begin with a thorough visual inspection of the power fold switch, wiring harness, and connectors. Look for any signs of damage, corrosion, or loose connections. Pay close attention to areas where the wiring harness may be rubbing against metal components. This is often the first step and can quickly identify obvious issues.

• Fuse Check: Check the fuse associated with the power folding mirror system. Consult your vehicle's owner's manual or a wiring diagram to locate the correct fuse. A blown fuse may indicate a short circuit and should be replaced with the correct amperage fuse. If the new fuse immediately blows again, it confirms a persistent short circuit.

• Switch Testing: Use a multimeter to test the power fold switch for continuity and proper operation. Refer to the vehicle's service manual or a wiring diagram to identify the correct terminals to test. The switch should show continuity in the appropriate positions and no continuity when it's not activated. An abnormal reading indicates a faulty switch.

• Wiring Continuity Test: Use a multimeter to check the continuity of the wiring harness between the switch and the control module. Disconnect the switch and the control module to isolate the circuit. Set the multimeter to the continuity setting (usually indicated by a diode symbol or a buzzer). Test each wire in the harness to ensure there is a continuous path between the corresponding terminals. Also, test each wire to ground to check for shorts. A short to ground will be indicated by continuity between the wire and the vehicle's chassis.

• Voltage Test: Verify that the switch is receiving the correct voltage. Use a multimeter to measure the voltage at the switch connector with the ignition on. Refer to the vehicle's service manual or wiring diagram for the correct voltage specification. A voltage reading that is too low or absent indicates a problem with the power supply to the switch.

• Component Isolation: This involves systematically disconnecting components in the circuit to isolate the short. First, disconnect the power fold switch. If the code clears or the symptoms disappear, the switch is likely the problem. If the problem persists, disconnect the mirror motor(s). This helps narrow down the location of the short.

• Scan Tool Diagnostics: Use a diagnostic scan tool to read any other related DTCs and monitor the power fold mirror system's parameters. A scan tool can provide valuable information about the circuit's behavior and help pinpoint the source of the problem.

• Wiring Diagram Reference: Consult the vehicle's wiring diagram to understand the circuit layout and identify specific wires and connectors. A wiring diagram is an essential tool for troubleshooting electrical problems. It shows the complete circuit, including all components, wires, and connectors.

Frequently Asked Questions:

• What does the B1717 code mean? The B1717 code indicates that the vehicle's computer has detected a short to ground in the power fold control switch circuit. This means there's an unintended electrical path to ground, disrupting the mirror's operation.

• Can I still drive my car with a B1717 code? Yes, you can typically still drive your car, but the power fold mirrors will likely not function correctly. While not a critical safety issue, impaired mirror functionality can reduce visibility.

• How much does it cost to fix a B1717 code? The cost depends on the cause. A faulty switch replacement might cost $50-$200, while wiring repairs or control module replacement could be more expensive, ranging from $200 to $800 or more.

• Is it possible to fix the B1717 code myself? Yes, if you have experience with automotive electrical systems and a multimeter, you can attempt to diagnose and repair the problem. However, professional diagnosis and repair are recommended if you are not comfortable working with electrical systems.

• Will a blown fuse cause a B1717 code? A blown fuse can be caused by the condition that sets the B1717 code. The short to ground is likely what caused the fuse to blow. Replacing the fuse without addressing the short will only result in the fuse blowing again.

Conclusion:

The B1717 code signifies a short to ground in the power fold mirror control switch circuit. Thorough troubleshooting, including visual inspection, component testing, and wiring checks, is crucial to identify and resolve the issue. Addressing this code promptly will restore the functionality of your power fold mirrors and ensure safe driving.