5 Volt Supply Output Too High (Chrysler)
What does P1497 mean?
The P1497 code means the vehicle's onboard diagnostic system has detected: 5 Volt Supply Output Too High (Chrysler). This is a moderate severity code.
Common Symptoms
- Check Engine Light illuminated
- Multiple sensor codes stored
- Engine runs rough or idles erratically
- Poor fuel economy
- Throttle response is delayed or jerky
Probable Causes (Ranked by Likelihood)
- PCM internal 5V regulator failure outputting high voltage Very High
- Short to battery voltage in the 5V reference wiring High
- Aftermarket device backfeeding voltage into the 5V line Moderate
- Corroded connector allowing voltage cross-feed Moderate
- Improper wiring repair causing crossed circuits Low
Step-by-Step Diagnostic Procedure
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Measure the 5V reference at multiple sensors. It should read between 4.9 and 5.1V. Above 5.2V confirms the issue.
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Disconnect the PCM connector and check if the voltage on the 5V reference line drops to zero. If it stays high, a wiring short is present.
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Check for aftermarket devices (tuners, gauge pods) connected to the 5V reference circuit.
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Inspect the wiring harness for cross-connections between the 5V reference and 12V power wires.
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If wiring checks good, the PCM 5V regulator is likely failed and the PCM needs replacement.
Frequently Asked Questions
Can high 5V reference damage sensors?
Yes. Sensors designed for 5V operation can be damaged by higher voltages. If the reference line is reading above 5.5V, sensors should be checked for damage after the root cause is repaired.
What causes the 5V to go too high?
The most common cause is an internal failure of the PCM voltage regulator that supplies the 5V reference. Less commonly, a wiring short to battery voltage can feed 12V into the 5V circuit.
Do I need a new PCM?
If all wiring checks out and no external devices are present, yes. The internal 5V regulator in the PCM is not serviceable and requires PCM replacement and reprogramming.