Transmission Mode Switch Circuit High
The P071F code indicates that the Powertrain Control Module (PCM) has detected a high voltage condition in the transmission mode switch circuit. This switch, often part of the manual shift or sport mode system, signals the PCM about the selected transmission mode. A high voltage reading typically points to a short to power, a faulty switch, or a wiring issue. This can cause incorrect transmission operation, such as erratic shifting or failure to engage the selected mode.
01. Most Common Causes
- Short to power in the transmission mode switch circuit
- Faulty transmission mode switch
- Corroded or damaged wiring/connectors
- PCM internal failure (rare)
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Transmission stuck in a single mode (e.g., sport or manual)
- Erratic or harsh shifting
- Inability to change transmission modes
03. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Visually inspect the transmission mode switch and wiring for damage, corrosion, or shorts.
Step 3: Test the switch resistance and voltage with a multimeter; compare to manufacturer specs.
Step 4: Check for shorts to power or ground in the circuit; repair as needed.
Step 5: Clear codes and test drive to verify repair.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive with this code as it can cause unpredictable transmission behavior, potentially leading to unsafe driving conditions or further transmission damage.
How much does it cost to fix?▼
The cost to fix P071F typically ranges from $50 to $150, depending on whether the issue is a simple wiring repair or requires replacing the transmission mode switch.