Heater Resistor - 4 Pin doesnt work in my car?!

[ATK 143 1 Cars]

Hi All

 

Anyone know if 4 and 5 pin heater resistors are interchangeable?

 

i thought they were but I put a new aftermarket 4 pin in my car which usually had a 5 pin and the 4 pin doesnt work?

 

duff unit..or not interchangeable?

[SRDT 189]

Looks like the wiring is the same aside from pin 3, maybe the control panel is special too despite looking the same on the diagram.

[Tom Fenton 1,557]

My understanding it that they are interchangeable but I haven't actually tried. The only difference is the 5 pin card has a bypass to give full voltage to the motor at max speed, the 4 pin always runs partly through the resistor.

 

Probably the new 4 pin is no good?

 

What is the matter with your 5 pin, they often have a bad contact and can be repaired.

[ATK 143 1 Cars]

Yeah, I thought all the 5 pin did was bypass the resistor. 
 

I repaired mine but it’s making a static/crackle sound so I was looking to stick a new one in