Heat flowing on passenger side only

If your sure you're looking at the right motor, Then the door is broke. Dash and plenum have to come out to fix it. Not a cheap fix.

DTC B1340 Air Mix Door #1 Movement Problem !
The heater and A/C programmer supplies voltage to an internal motor that drives the air mix door. The heater and A/C programmer monitors the air mix door position feedback from a sensor on the motor. If the air mix door is requested to move but the feedback voltage does not change, the heater and A/C programmer will store DTC B1340. If the air mix door feedback indicates that the feedback is near the hot or the cold extreme, the DTC will not set. Evaluate the operation of the air mix door through self diagnostics as described in the test description.
Test Description
Perform the Diagnostic System Check before continuing with the diagnosis of this DTC.
A Scan Tool allows for the direct control of the air mix door by observing the following conditions:
• The air mix door position feedback value
• The value`s difference from the air mix door commanded position value
These readings indicate a fault internal to the heater and A/C programmer in the air mix door sensor feedback.

Did you perform the Diagnostic System Check?
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Go to Step 2
Go to Diagnostic System Check
2
With the engine running, connect a Scan Tool .
Turn the dual zone to OFF (passenger temperature offset at 0 or OFF).
Exercise the suspect actuator using the temperature control on the control assembly.
Is the door being commanded (COM) to the proper high and low values?
COM High 100 %
COM Low 0 %
Go to Step 3
Go to Step 4

If you are unfamilier with this , i suggest you take it to a ASE certified repair shop or the dealer .

Here's is a little background and a couple of thoughts. Turning to the background, first. The heater/air conditioner system in your 02 uses the same set of ducts located in the instrument panel. In turn, those ducts are linked to what can be considered miniature version of the cooling system in the engine compartment (yes, this is a greatly simplified version). The whole system, in fact, is run off the main heater/ac system, however, it has a separate series of controls so that it can function properly.

When you dial a temperature, a signal is sent to the heater/cooling system telling the system to open a series of baffles, directing a flow of heated or cooled anti-freeze/coolant to the proper "radiator" behind the face of the instrument panel. In turn, the fan system activates a series of doors behind the instrument panel so that the flow of air is directed through the "radiator" and into the passenger compartment. This is essentially the heater/cooling system work.

Now, you say that the driver's side is hot, while the passenger side is cool. What has happened is that the flow of heated coolant that is supposed to heat the passenger side of the duct system is blocked. Since there is no heat to warm the air that is flowing past the fins of the "radiator," the flowing air remains cool to cold, depending on the weather and ambient temperature. The result is that one side of the car remains cool. And, since the other side of the "radiator" is normal and the air is heated, it is warmed.

That is the most likely explanation for this.

Another possibility is that the baffles themselves are stuck and the coolant that is supposed to be directed to the passenger side is not being directed their.

Either way, your technician has some work ahead.

The actuator door that is behind the dash that closes off the heater core from shooting hot air thru the vents might be your problem. When you turn on your ac the actuator shuts the door to prevent the air from flowing thru the heater core into the cabin, this may be your problem if everything else is working properly. Let us know.

There is a blend door problem.

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HEATING AND AIR CONDITIONING Refer to Section 1 for discharging and charging of the air conditioning system. The heating system provides heating, ventilation and defrosting for the windshield and side windows. The heater core is a heat exchanger supplied with coolant from the engine cooling system. Temperature is controlled by the temperature valve which moves an air door that directs air flow through the heater core for more heat or bypasses the heater core for less heat. Vacuum actuators control the mode doors which direct air flow to the outlet ducts. The mode selector on the control panel directs engine vacuum to the actuators. The position of the mode doors determines whether air flows from the floor, panel, defrost or panel and defrost ducts (bi-level mode).

Just had this happen today to my 2007 silverado heat on the right side cold air on the left side. After engine was off 15 minutes and restarted heat was on both sides. I'm guessing a relay failed to open door to allow the heat to flow thus blowing cold air.will monitor diligently for a while.

I had the same problem when i was working on my 1999 Buick Regal and had to disconnect the battery. I didn't reconnect in the same way that I disconnected the battery from the terminal and noticed that the driver side had no heat or air but the passenger side did. I then disconnected the battery again and reconnected it the same way and now have heat and air on both the driver and passenger side. Hope this helps. Good Luck!

This may be one or two different problems. One could be the climate control unit itself. Surprisingly the problem with the air not changing the source will likely be remedied by a reprogramming by a Volvo dealer. Defrost is the delfault outlet if there is a problem with that system. As for the dial not having detents and the cold instead of hot air in the pass side, that could be programming, a disconnect with the heater door for the passenger side or it could be the control unit. 98 is a difficult year to diagnose and the dealer is likely the only one who can properly diagnose this car. The download at the dealer is an inexpensive fix. If there is a mechanical problem within the air system that could prove more costly. I'm not sure how much the control unit for the climate control system, but there are usually quite a few on ebay. Good luck and I would suggest visiting the dealer first for this one as it is the least expensive fix and could very well be the only problem.