What it means
Control Module Input Power A Circuit Range/Performance: the signal is implausible or outside the valid range.
At a glance
- Usually lights the warning light of the system that lost communication
How it works
Input Power A is a monitored supply circuit feeding a control module. The module checks whether that supply behaves within its valid range; this code sets when the signal is implausible or outside the expected range, which can cause communication or function problems.
Common causes
Most likely first.
- High resistance in supply path
- Gateway module routing CAN messages incorrectly
- CAN terminating resistor (120 Ω) drifted out of spec
Symptoms
- Multiple warning lights may illuminate
- Affected modules may go into limp mode or shut down
- Specific functions inoperative depending on module
- Diagnostic tools may show communication faults
How to diagnose it
- Scan all modules and note whether several report power or communication faults, which can indicate a shared supply problem.
- Review freeze-frame and live data for Input Power A status and the battery or charging state when the fault occurred.
- Inspect the Input Power A fuse, wiring, connectors, and grounds for corrosion, looseness, heat damage, or high resistance.
- Measure the supply under the conditions that trigger the code and compare it with the manufacturer's specification, checking voltage drop along the circuit.
- If the supply path is sound, inspect gateway routing and CAN network termination for separate communication faults.
Common fixes
- Clean and secure corroded or loose Input Power A connections and grounds.
- Replace a failed fuse after checking for a short or overload.
- Repair high-resistance or damaged supply wiring.
- Repair a confirmed gateway routing or CAN termination fault if the power circuit tests correctly.
Can I keep driving?
If several systems are failing or the vehicle enters limp mode, avoid driving until the power supply fault is checked. An unstable module supply can cause further shutdowns or loss of vehicle functions.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.