12 Volt Battery And/Or Hybrid Battery Going Dead Overnight With Or Without DTC P2535 – 2016-2019 Cadillac CT6

SEOCONTENT-START

Bulletin No.: PIC6355A Published date: 07/23/2019
Preliminary Information
PIC6355A Diagnostic Tip For 12 Volt Battery And/Or Hybrid Battery Going Dead Overnight With Or
Without DTC P2535
Models

Brand: Model: Model Years:

VIN:
from to

Engine: Transmissions:

Cadillac CT6 2016 – 2019 All All
All All

Involved Region or
Country North America
Condition
Some customers may experience one or all the following concerns.
1) Battery draw which typically is between 200mA to 1500mA
2) Current or history DTC: P2535
3) Dead 12V battery
4) Depleted high voltage battery range. ( Hybrid Models Only )
Cause
Concern may be caused by a backfeed in voltage on one of the circuits that are powered by the KR73
Ignition Main Relay
Correction:
If you experience one or the above concerns and you can not isolate the concern following SI
diagnosis, check for voltage with a DVOM on all the fuses that are feed by the KR73 Ignition relay.
See example of circuits supplied by KR73 Ignition relay by refering to Service Information Document
F5UA, F27UA, F28UA, F29UA, F40UA, F42UA, and F43UA found under Power Distribution Schematics.
If there is any voltage on the fuses with the ignition in the off position, remove fuses one at a
time to isolate which module is causing the concern. Once you have located the effected module,
Unplug the module and see if the back feed goes away. Once the module is isolated, replace as
needed.
TAC has seen some issues in the field where the K29F front heated seat module or the K29R rear
heated seat module may be causing the concern.
Version History
Version 2
Modified 03/12/2019 – Created on.

07/23/2019 – Updated to change document referral to new
process

SEOCONTENT-END