Once again, the colder days are closing in on us, and I see an increase of threads like "Heaters", "Blowers", "Internal Fans not working"
This topic keeps rearing its head every year about this time, so I thought a guide on how to fix this should be written.
So, if your heaters are not working, then read on. Does your blower only work on its highest setting? read on.
Firstly, you need to find out which heater system you have. Ph1 (mainly before 1994) have heaters with 3 speed settings, and ph2 (post 1994) have 4 settings.
Pre 1994
Post 1994
This is important, as the 2 variations require a different resistor pack.
"Resistor pack ?" I hear you say. Yes, this is the part that has most probably died on you. The heater blower speed is controlled by reducing the amount of power going to the blower motor. At a full 12v, you get full speed. By passing the 12v through various resistors, less power getts to the motor and the blower fan turns slower. If the resistor pack stops working, all you have is the setting with the full 12v, where the power does not pass through the resistor pack. This is why, if your heater only works on full speed, be it 3 or 4, then your are most likely looking at a broken resistor pack.
Why do they break?" is your next question. Because Opel/Vauxhall made a bad design, and fitted the resistor pack somewhere damp and wet. The resistor pack doesn't like this. The connections start to corrode away first, then eventually the whole pack just rusts from the inside and the whole thing stops working.
This is a resistor pack.:
Top Tip: The resistor pack in other Vauxhalls/Opels differ from shape, and cant be fitted permanently eg, the Corsa B resistor pack can't be fitted into the Astra Mk3, but the electrical fittings ar the same, so if you only have one from a different car you can still test the system to make sure it is the resistor pack you need to change.
A new resistor pack looks like this:
Note the amount of pins. A 3 speed blower has 6 pins, and a 4 speed blower has 7 pins (as shown in the picture)
Now you know what has failed, and what it looks like. Where is it?
The resistor pack is found under the pollen filter, here:
You can access it without taking the windscreen wipers and scuttle panel off, but it is easier to replace it if you do take the wipers and scuttle panel off. Because the pins corrode so well, it can be difficult getting the plug off the resistor pack. Once you take off the pollen filter you will see it:
To remove it you should:
Now fit the new resistor pack, and replace everything in reverse order. That should cure your heater problems.
Hope this helps you through the next winter
Jason
If you want this as a PDF, then click here:
www.madhaus.de/resistor.pdf
This topic keeps rearing its head every year about this time, so I thought a guide on how to fix this should be written.
So, if your heaters are not working, then read on. Does your blower only work on its highest setting? read on.
Firstly, you need to find out which heater system you have. Ph1 (mainly before 1994) have heaters with 3 speed settings, and ph2 (post 1994) have 4 settings.
Pre 1994
Post 1994
This is important, as the 2 variations require a different resistor pack.
"Resistor pack ?" I hear you say. Yes, this is the part that has most probably died on you. The heater blower speed is controlled by reducing the amount of power going to the blower motor. At a full 12v, you get full speed. By passing the 12v through various resistors, less power getts to the motor and the blower fan turns slower. If the resistor pack stops working, all you have is the setting with the full 12v, where the power does not pass through the resistor pack. This is why, if your heater only works on full speed, be it 3 or 4, then your are most likely looking at a broken resistor pack.
Why do they break?" is your next question. Because Opel/Vauxhall made a bad design, and fitted the resistor pack somewhere damp and wet. The resistor pack doesn't like this. The connections start to corrode away first, then eventually the whole pack just rusts from the inside and the whole thing stops working.
This is a resistor pack.:
Top Tip: The resistor pack in other Vauxhalls/Opels differ from shape, and cant be fitted permanently eg, the Corsa B resistor pack can't be fitted into the Astra Mk3, but the electrical fittings ar the same, so if you only have one from a different car you can still test the system to make sure it is the resistor pack you need to change.
A new resistor pack looks like this:
Note the amount of pins. A 3 speed blower has 6 pins, and a 4 speed blower has 7 pins (as shown in the picture)
Now you know what has failed, and what it looks like. Where is it?
The resistor pack is found under the pollen filter, here:
You can access it without taking the windscreen wipers and scuttle panel off, but it is easier to replace it if you do take the wipers and scuttle panel off. Because the pins corrode so well, it can be difficult getting the plug off the resistor pack. Once you take off the pollen filter you will see it:
To remove it you should:
- Remove the windscreen wipers
- Remove the scuttle panel
- Remove the pollen filter by releasing the 2 retaining clips
- Undo the 2 retaining screws holding the resistor pack in place
Now fit the new resistor pack, and replace everything in reverse order. That should cure your heater problems.
Hope this helps you through the next winter
Jason
If you want this as a PDF, then click here:
www.madhaus.de/resistor.pdf
Last edited:
) - the original (184 degrees) has failed, so I replaced it with another one, rated at 157. Hope this helps.
