The heater core allows hot coolant to past through the ventilation system and warm the air. When one is clogged or damaged, the heater will no longer work. Learn how to replace the heater core here.
This article applies to the Chevrolet Silverado 1500 (1999-2006).
The heater core is as it sounds: the heart of the climate control system in your Chevy Silverado. It is essentially a mini radiator hidden deep inside the engine compartment behind the dashboard, which produces heat for the climate system. The heater core has coolant lines which connect to it and produce the actual heat. A fan then pushes the heat through the ventilation system and into the cabin. If a heater core gets clogged or the blend door becomes jammed, the unit will need to be removed. This task is not for the faint of heart and requires the complete removal of the dashboard, including the radio, airbags, and climate control system. However, this article can assist you in getting the job done and prevent that hole in your pocket from getting any bigger.
Materials Needed
- Metric socket set
- 3/8" ratchet
- Coolant
- Pliers
- Drain pan
- Screwdriver
- Shop rags
Step 1 – Remove the dashboard cover
The dashboard on your Chevy is installed piece by piece; the first part you will be removing is the upper dashboard cover.
- Disconnect all the wire plugs that connect to the dashboard.
- Gently lift the dashboard cover up and disconnect the ambient light sensor.
- Remove the dashboard cover.
Step 2 – Begin disassembling the dashboard components
- Remove the 7mm vent register bolts.
- Remove the vent register assembly.
- Remove the passenger side air bag switch.
- Loosen and remove the steering column bolts.
- Then, remove the steering column covers and steering wheel.
Step 3 – Finish removing the remaining dashboard components
- Pull the rear cup holder out as far as it goes.
- Lift the pocket of the center console up.
- Locate the four mounting bolts and remove them.
- Remove the center console.
- Remove the antenna and radio.
- Remove the wire harness clips from the interior cabin.
- Remove the instrumental panel cluster.
- Remove the parking brake release lever.
The passenger side airbag also needs to be removed.
- First disable the SRS system.
- Then remove the upper and lower 10mm airbag mounting bolts.
Some vehicles are equipped with optional accessories including the OnStar safety system; refer to Figure 15 for its removal.
- Locate the communication interface module and remove the three 10mm mounting bolts.
- Remove the unit.
Step 4 – Empty the climate control system
- Drain the coolant from the system and evacuate the air conditioning system.
Step 5 – Replace the heater core
- Unbolt the HVAC assembly.
- Remove the heater core cover screws.
- Replace the heater core.
- Install the cover.
- Mount the assembly back onto the truck.
Step 6 – Re-install everything
Once the deed is done, take your time and re-install all of the dashboard components. Be wary of the screws and bolts you use to re-install the components, as some are slightly longer and will not fit all the way in. After everything is back together, top off the coolant and reconnect the negative battery cable.
Figure 21. Dashboard re-installed.Related Discussions and Sites
- 2001 Silverado Heater Core - Chevroletforum.com
- Heater Problem - Chevroletforum.com
- Changing a Heater Core PICS - Performancetrucks.net
- 2004 Chevrolet Silverado, Dash Cover Removal - Sparkys-answers.com
What is a heater core?
The heater core looks like a very small radiator, and functions just the same. It's mounted under the dashboard, and it provides the heat needed for the blower motor to warm the cabin.
How does the heater core work?
Hot engine coolant circulates through the heater core. When the driver turns on the heat, the blower motor blows air across the heater core and into the cabin.
What are the symptoms related to a bad heater core?
A failing heater core may cause the car's interior to smell like engine coolant. The smell will become worse when the heater is turned on. The engine may also begin to run hotter until the vehicle is repaired.
The worst-case scenario is the engine overheating, which can cause extensive engine damage.
If the heater core is clogged, the air that blows when the heater is turned on will not be very hot.
Can I drive with a heater core problem?
If the heater core is leaking, don't drive the car. Any coolant leak can lead to an overheated engine. In this situation, towing the vehicle to a repair facility is the best course of action.
When the heater core is clogged, it will not affect drivability, but passenger comfort may suffer.
How often do heater cores need to be replaced?
Most vehicles will never have a problem with the heater core. But if you don't have your cooling system maintained and flushed as part of the car's regular maintenance, the odds of a heater core problem go way up.