Fuel Injector Group Supply Voltage Circuit High
The P2157 code indicates that the powertrain control module (PCM) has detected a voltage level in the fuel injector group supply circuit that is higher than the specified range. This circuit provides power to a group of fuel injectors, and a high voltage condition can be caused by a faulty injector driver, a short to voltage in the wiring, or a malfunctioning PCM. This can lead to excessive fuel delivery, causing rich running conditions, poor fuel economy, and potential engine damage.
01. Most Common Causes
- Faulty fuel injector driver in PCM
- Short to voltage in injector group wiring
- Corroded or damaged connector
- Failed PCM
02. Symptoms You Will Notice
- Check Engine Light on
- Engine misfire or rough idle
- Poor fuel economy
- Black smoke from exhaust
- Engine stalling
03. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Visually inspect injector group wiring and connectors for damage or corrosion.
Step 3: Measure voltage at injector group supply circuit with key on; compare to spec (typically battery voltage).
Step 4: Check for shorts to voltage using a multimeter; isolate circuit and test resistance.
Step 5: If wiring is OK, test injector driver output from PCM; replace PCM if faulty.
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 engine damage due to excessive fuel delivery. Have it diagnosed and repaired promptly.
How much does it cost to fix?▼
The cost typically ranges from $150 to $400, depending on the cause. Wiring repairs are cheaper, while PCM replacement is more expensive.