Ridiculous Texas Heat Seemingly Fried This Chevy HHR But I Don’t Know How

Likely several things here but with things getting hot and not working and then working again points to a thermal problem. I remember 80’s and 90’s GM ignition control modules that would get hot, shut down and kill the spark. By the time AAA arrived, it had cooled down enough to start working again.

In this case, I’d be looking at the Body Control Module (BCM). It’s on the right side of the center console. I dont think that little scanner can read B codes and they wont turn on the MIL but I bet there’s some stored. If you can get a scanner that will pull B, C and U codes that would be the first thing I’d check.

Here’s description and operation of the body control system from the GM manual for this thing and you’ll see it controls a LOT.

Body Control System Description and Operation

The body control module (BCM) has a bussed electrical center integrated into the housing. Body control relays and fuses are installed directly on the BCM, which simplifies wiring and junction blocks on the vehicle. The body control system consists of the BCM and its associated controls. Battery positive voltage is provided to the BCM from IBCM BATT 1 fuse and the IBCM BATT 2 fuse in the underhood fuse block. The module grounds are wired to ground G201, G203 and G305. The BCM is wired to the GMLAN High speed serial data buss, and the GMLAN Low speed serial data buss, as well as discrete input and output terminals to control the functions of the vehicle’s body.

Serial Data Gateway

The body control module (BCM) in this vehicle functions as a translator between the High and Low speed GMLAN busses. The 2 communication protocols use the BCM to translate communicated serial data messages between the control modules over the 2 serial data busses.

Power Mode Master

This vehicles body control module (BCM) functions as the power mode master (PMM). Refer to Power Mode Description and Operation (See: Power and Ground Distribution > Components > Power Mode Description and Operation) for a complete description of power mode functions.

Body Control Module

The various body control module (BCM) input and output circuits are described in the corresponding functional areas indicated on the BCM electrical schematics. The BCM functions include the following:

* A/C compressor request-Refer to Content Theft Deterrent (CTD) Description and Operation (See: Antitheft and Alarm Systems > Components > Content Theft Deterrent (CTD) Description and Operation) for the manual system.

* A/C cooling fan-Refer to Air Delivery Description and Operation (See: Heating and Air Conditioning > Components > Air Delivery Description and Operation) for the manual system.

* Battery rundown protection (inadvertent power)-Refer to Interior Lighting Systems Description and Operation (See: Lighting and Horns > Components > Interior Lighting Systems Description and Operation).

* Bulb check-Refer to Instrument Cluster Description and Operation (See: Instrument Cluster / Carrier > Components > Instrument Cluster Description and Operation).

* Chimes-Refer to Indicator/Warning Message Description and Operation (See: Instrument Panel, Gauges and Warning Indicators > Components > Indicator/Warning Message Description and Operation).

– Check gages

– Door ajar warning

– Headlamps ON

– Key-in-ignition

– Oil reset

– Park brake warning

– Seat belt not fastened

– Turn signal ON

* Door lock interface-Refer to Power Door Locks Description and Operation (See: Power Locks > Components > Power Door Locks Description and Operation).

* Electronic power steering (EPS)-Refer to Power Steering System Description and Operation (Non-Turbo) (See: Steering > Components > Power Steering System Description and Operation)Power Steering System Description and Operation (Turbo) (See: Steering > Components > Power Steering System Description and Operation).

* Engine coolant level sensing-Refer to Cooling System Description and Operation (See: Cooling System > Components).

* Exterior and interior lighting control-Refer to Exterior Lighting Systems Description and Operation (See: Lighting and Horns > Components > Exterior Lighting Systems Description and Operation).

– Automatic lighting control

– Daytime running lamps (DRL)

– Fog lamps

– Park brake lights

– Turn hazard lamps

* Gage control-Refer to Instrument Cluster Description and Operation (See: Instrument Cluster / Carrier > Components > Instrument Cluster Description and Operation).

* Horn interface-Refer to Horns System Description and Operation (See: Horn > Components > Horns System Description and Operation).

* Instrument cluster indicator control-Refer to Instrument Cluster Description and Operation (See: Instrument Cluster / Carrier > Components > Instrument Cluster Description and Operation).

* Interior lighting-Refer to Interior Lighting Systems Description and Operation (See: Lighting and Horns > Components > Interior Lighting Systems Description and Operation).

* Key-in-ignition sensing-Refer to Indicator/Warning Message Description and Operation (See: Instrument Panel, Gauges and Warning Indicators > Components > Indicator/Warning Message Description and Operation).

* Parking brake state sensing-Refer to Brake Warning System Description and Operation (See: Hydraulic System, Brakes > Components > Brake Warning System Description and Operation).

* Retained accessory power (RAP)-Refer to Retained Accessory Power Description and Operation (See: Power and Ground Distribution > Components > Retained Accessory Power Description and Operation).

* Rear compartment interface-Refer to Power Door Locks Description and Operation (See: Power Locks > Components > Power Door Locks Description and Operation).

* Rear defogger-Refer to Rear Window Defogger Description and Operation (See: Windows > Components > Rear Window Defogger Description and Operation).

* Remote function control-Refer to Keyless Entry System Description and Operation (with Accessory 2 Way Remote) (See: Keyless Entry > Components > Keyless Entry System Description and Operation (with Accessory 2 Way Remote))Keyless Entry System Description and Operation (without Accessory 2 Way Remote) (See: Keyless Entry > Components > Keyless Entry System Description and Operation (without Accessory 2 Way Remote)).

* Seat belt use sensing-Refer to Seat Belt System Description and Operation (See: Seat Belt Systems > Components > Seat Belt System Description and Operation).

* Content theft deterrent-Refer to Content Theft Deterrent (CTD) Description and Operation (See: Antitheft and Alarm Systems > Components > Content Theft Deterrent (CTD) Description and Operation).

* Vehicle theft deterrent-Refer to Content Theft Deterrent (CTD) Description and Operation (See: Antitheft and Alarm Systems > Components > Content Theft Deterrent (CTD) Description and Operation).

* Washer solvent level sensing-Refer to Wiper/Washer System Description and Operation (Front ) (See: Wiper and Washer Systems > Components > Wiper/Washer System Description and Operation (Front ))Wiper/Washer System Description and Operation (Rear) (See: Wiper and Washer Systems > Components > Wiper/Washer System Description and Operation (Rear)).

* Wiper/washer-Refer to Wiper/Washer System Description and Operation (Front ) (See: Wiper and Washer Systems > Components > Wiper/Washer System Description and Operation (Front ))Wiper/Washer System Description and Operation (Rear) (See: Wiper and Washer Systems > Components > Wiper/Washer System Description and Operation (Rear)).