P0D17: Battery Charging System A High Voltage Interlock Circuit Low

P0D17 means the sensed voltage of the charging HVIL loop is too low. GM documents the check for the Chevrolet Volt (2011, 2014) and the Cadillac ELR: while the module sources 5 V into the loop, a sensed value under 30 % of the reference in two samples out of two at 12.5 ms sets the code as Type A, with the MIL on after one trip. A low reading suggests a path to ground or leakage somewhere in the loop wiring, or a fault in the measuring stage of the module. Because the test only runs with the source switched on, it typically shows up around charging. The interlock of battery and drive has its own code, P0A0C. P0D18 is the high counterpart, P0D15 the open loop. With an implausible loop the car refuses to charge.

High severity. Can I keep driving?If the car still runs, drive as little as possible and go to a specialized repair shop. Do not touch the orange cables: they carry high voltage.

Symptoms

Malfunction indicator lamp after one trip (GM Type A)
Charging refused

Most likely causes

Interlock wire chafed and touching ground
Moisture or dirt in an interlock connector causing leakage
Fault in the interlock source or measuring circuit of the control module

What to check, in order

Start with the simplest. You can tick off each step.

Read the codes with a hybrid-compatible scanner and write down the freeze frame data
With the connector unplugged, check whether the signal wire is making contact with ground.
Make sure the battery cooling air intake is clean
Check the 12 V auxiliary battery, which can also trigger warnings
Leave any high-voltage measurements to a specialized repair shop

Good to know

Repair difficulty: medium

What each character of P0D17 means

P: Powertrain: engine and transmission
0: Generic code: same on every make
D: Subsystem depends on the code range
17: Specific fault in that system

Frequently asked questions

Can I keep driving with code P0D17?

If the car still runs, drive as little as possible and go to a specialized repair shop. Do not touch the orange cables: they carry high voltage.

What causes code P0D17?

The most common causes are: interlock wire chafed and touching ground; moisture or dirt in an interlock connector causing leakage; fault in the interlock source or measuring circuit of the control module.

Related codes

Sources

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.