Heater does not work

Well check the fuses first.

If the fuses are fine, check if the blower motor is receiving a power and ground signal when the blower fan is turned on.

Check out this guide

https://www.2carpros.com/articles/car-heater-not-working

Please run down this guide and report back.

Was the thermostat checked? Was the system bled of air? This guide can help.

https://www.2carpros.com/articles/car-heater-not-working

Please run down this guide and report back.

Are both hoses to and from the heater core hot?

This indicates coolant is not flowing and it could either be due to clogging of the heater core or the hoses are not installed correctly.

It could also be due to the thermostat sticking in the open position or a weak water pump.

When flushing the heater core, were the flushing water coming out strongly?

How to Retrieve a Diagnostic Trouble Codes
The Heater Control Panel has a self-diagnosis function. To run the self-diagnosis function, do the following:
Turn the ignition switch OFF.
Turn the fan switch OFF, the temperature control dial on Max Cool and the mode control dial on Vent.
Turn the ignition switch ON (II), then press and hold the recirculation control switch. Within 10 seconds while holding the switch down, press the rear window defogger switch five times. The recirculation indicator blinks two times, then the self-diagnosis will begin. If there is any problem in the system after self-diagnosis is finished, the recirculation indicator will blink the Diagnostic Trouble Code (DTC) 7 through 13. When problems in the evaporator temperature sensor circuit are detected (codes 14 and 15), the A/C indicator will blink the DTC. If no DTC's are found, the indicator will not blink.
Fig. 7: Retrieving DTC
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Fig. 8: Example Of DTC Indication Pattern (DTC 7)

Canceling the Self-diagnosis Function
Turn the ignition switch OFF to cancel the self-diagnosis function. After completing repair work, run the self-diagnosis function again to make sure that there are no other malfunctions.
Max Cool Position Function
When the mode control dial is in the MAX A/C position, the heater control panel will automatically select the Recirculation mode and turn the A/C on. The recirculation switch and A/C switch are disabled and cannot be turned off in this mode. If the control panel fails to function as described, replace it.

If the water had good flow, then it should not be a clogged heater core. Check the hoses for clogging.

Recheck the thermostat, ensure it is not sticking in open position. Remove radiator cap and while running note if the coolant are circulating when engine is cold.

Hi thrityshark,

If the blower fan is not working, it most probably is caused by a failed motor.

Give the housing under the dash some gentle banging with your fist to check if the motor starts running, if yes, the motor is due to be replaced.

When you are stopped at a light put the vehicle into neutral and revv it up, does the incoming air get colder?

And yes this is an a/c problem. I've seen loose belts and low refrigerant cause this.

Hi there,

Thank you for the donation,

Check that the heater hoses coming from the engine into the cabin are both hot to touch with the heater on and engine at normal operation temp. If not, you have no flow through the heater core, this may be due to a blocked core or a faulty heater tap, check this out first.

Mark (mhpautos)