08 Chevy HHR Fuse 26 Constantly Blowing

Hey gang,

Fuse 26 constantly blows out. I think it might be from AC use, but I can’t be sure. It’s literally blown when I was sitting in the far, air off, ac off, just idling. Only happens in the summer. Any help or place to start that doesn’t involve thousands to a mechanic would be awesome.

If you want to try and solve the trouble yourself then you would be wise to invest in a factory service manual that at least covers the wiring for the car. It is a good investment to make if you want to work on problems like this. Ebay is a good place to get one from. The manual will show you how all the fuses are connected to the devices in the car and where to locate things on the car.

Which fuse block is this blown fuse in?
In the underhood fuse block, item 26 is a relay, not a fuse, known as the PWR/TRN relay. It supplies power to three or four fuses and the coil of the A/C clutch relay.
In the BCM or console fuse block, fuse 26 is for the door locks.

Beware of some of those manuals on eBay. They are probably unauthorized (copyright infringing) copies.

Your owners manual will give some info about which devices are served by which fuse or relay. That can get you started. Good advice, above, about hoped-for more complete information, which may be helpful.

On some cars the AC compressor turns on not only when you have the AC on, but when you have the controls on a mix of air to the cabin AND defrost.

Fuse #26 protects the circuit to the PWR/TRN relay #26 in the fuse box under the hood.


You really need a good wiring schematic to examine first. Preferably something laid out in a current flow format. Otherwise, you end up wandering around mostly blind and spending a lot of time along with getting frustrated.

If this fuse powers a relay and the trouble is on the circuit the relay supplies power to then you can remove the relay to see if the short goes away. That will prove the short is on that path at least.

I don’t see a fuse 26 in the underhood fuse block label diagrams or the electrical schematics. Terminals 86 (coil +) & 87 (relay switch +) of the PWR/TRN relay appear to be directly supplied by the fuse block B+ bus. Terminal 85 (coil -) is connected directly to the ECM.

it’s to the door locks.

That helps. This fuse supplies power to the 3 door lock relay coils and switches, then through the relay switches to the door latches.
If the fuse blows spontaneously with the electric door locks not in use, there must be some sort of intermittent short within the BCM or the lock relays.
If the fuse only blows when using the door locks, then there could be a short within the BCM, relays, the wiring to the door latches, or the latch lock solenoids.

Here’s a wiring diagram (click to blow up).

Fuses usually supply power to a number of things, not just one individual circuit. It could be that this fuse is only used for the door locks but I doubt that is the case. I don’t have any data to refer to unfortunately.