I have a 92 Volvo 960Wgn. I am having problems with the climate control and blower motor. I have no blower at this time and with winter coming I need heat now. I followed the diagnostic instructions and the code reads 233. Which means "Excessive Starting Current"
What does that mean? Motor is fried? Is there a voltage regulator or something similar? Other?
Any help is appreciated.
Lee

 

960's have their own forum, you posted this in the 240/740/940 forum, those cars never had ECC, just manual hvac...

but my guess is, thats either an electrical problem in the ECC control unit, or your blower motor is dead or jammed. my wife had a 960 and it sucked up some tissue that was on the passenger floor, and jammed its fan, I had to do fairly major dashboard surgery to get it out, ugh.

I'm going to move this thread to the 960 forum, as they are undoubtably better equipped to answer, its been 10+ years since our 960 went to the car graveyard (bent by being tail ended)

 

Thanks Pierce, sorry for the error.

 

Replaced the climate control unit but still nothing and the code is still 233. So now I am looking at replacing the blower motor. But before I do does anyone have any other suggestions? Any other relays or resistors I should look at first?

 

probably the motor. drop the passenger side kick panel, remove the glovebox, and the blower is inside that big drum back there. IIRC, it can be removed out the bottom (at least on a 740/940 it can, its been so long since we had a 960 I forgot).

 

Thanks Pierce. I will try and hot wire the motor with a battery to see if it works, if not, is there any replacement motor that I can use other than an OEM Volvo?

 

looks to be PN volvo 3537857 for the fan+motor assembly on the 1992 960's.

and yeah, looks like there's offbrand replacements
Volvo HVAC Blower Motor (760 940 960 S90 V90) - Four Seasons 3537857 | FCP Euro

or the real Volvo part,
Volvo Parts - TascaParts.com

 

Got a new blower motor and when removing the old motor I noticed the electrical plug for the blower was burnt on the ground side. I plugged in the new motor and it ran until I hit5{speed} and then it blew the fuse. Is there a relay or resistor for this blower motor? I am not having much luck finding one. It is a 1992 960 with ECC. Thanks

 

no resistor, but there's a power module "2/10" on the diagrams, part number 1365678, appears to be on the top of the fan housing.

power from fuse 28, 2 violet wires, one goes to the fan pin 1, and the other goes to power module pin 1B. fan pin 2 is a blue-black wire to power module pin 1A. power module pin 2A goes to ground, 3B, 4B, and 6B go to the ECC controller and control how much power the fan gets. pin 2B goes to the sensors and AC compressor.

 

Not having any luck locating that part. I did find a resistor but can`t get a human too ask if it the right part. I found mine, just can`t find one on the net. Help?

 

part 15 on here,
Heater unit 960.. Fits: Volvo | VolvoPartsWebstore.com

 

Thanks Pierce, had a local Volvo Dealer look for it but no longer available.
I am working with a bone yard, hopefully they have one. Is there a way to test mine? Got it apart for a visual but everything looks good, no broken solder joints anyway and no burning. Will have my neighbor check it out with ohm meter. But any suggestions are welcome.

 

hmm? this Volvo dealer says its available
Control unit. Heater unit; Heater unit 960 e. C. C -1994; Heater unit 960. Volvo # 1365678

note thats an electronics module, so not going to be easy to test with a volt meter. the block diagram shows it has a couple relays inside, and a darlington power transistor but thats generally just a rough concept view, not an actual internal schematic.

 

Thanks a Ton Pierce,I truly appreciate your help. I have mine out and removed the cover and inspected the board. Nothing appears wrong visually. No burnt board or broken solder joints. I realize that a bad resistor can be internal or the same with the other components, just hate to spend $225 more and that not being the problem. Becasue the code reads excessive starting current I think this is the problem, does it make sense too you?

 

If you can trace the blue wire from the fan then you will find the power control box.

If you can ground the blue wire from the back of one of the connectors the fan should come on full blast bypassing the power module. Will the fuse burn again if you do this?

How does the ECC know the blower motor current? Is it wire B6 from the power module? Even though I have a later car, I am interested in knowing how it works because there are fewer details on the wiring diagram for my car.

I think that some multimeter testing is possible.
first, actual current measurement of the blower motor by itself.

The power box can be probed in situ. The block diagram shows enough of what it does but there may be more resistors or passives in the box.

I think that 3B is the blower full speed coil. When the blower speed is on max the ECC will ground this wire, and there should then be a resistance of less than 1 ohm between 1A and 2A (unplug connector A for this)

BUT what about that burnt connector? is it a bad connection? Resistance means current (and heat)

 

IIRC from when I had a 960, the fan didn't turn on instantly, it smoothly ramped up in speed. this would have to be done via PWM (pulse width modulation) via that darlington transistor I described, where the ECC control box triggers the darlington with a changing duty cycle. this reduces the initial inrush current since the motor starts up slowly. once its up to full speed, it could switch on that relay and turn off the transistor.

the schematic I have showed at least one more connection from the power module to the ECC controller than I would think are needed to implement its functionality (not counting the AC compressor relay part), that extra signal, directly to the low side of the fan, could be used for monitoring?

 

Here is what I figured out for the 1365678 power box. It is used in some 760, many 940, 960, S/V90. On my S90 the compressor relay is not used, they placed another relay underhood for the compressor.

This info is not complete hopefully we can figure out the "not sures" Is there a pinout or "signal description" for the ECC connector in one of the books?

A:
1 - Transistor collector (blue fan wire)
2 - Transistor emitter (ground)

B:
1 - B+ for 3B, 2B, 5B
2 - Compressor Clutch output
3 - ?? Fan Full Speed (pretty sure but not 100%)
4 - Transistor base (PWM speed control from ECC)
5 - Compressor clutch coil (connect to ECU compressor signal)
6 - ?? Fan voltage sensing (should be a low resistance path to 1A)

I'm thinking that the burnt connector is a big clue about Lee's issue.

 

I certainly appreciate all your wisdom you guys, but you are way over my head. Here is what I learned yesterday. The control module appears to be OK visually. My neighbor who is pretty good with stuff like this also pointed to the burnt wire which he says is a ground. He instructed me to take a new wire and ground it and touch the same contact that the burnt one was on. So I did this and I got spark where I grounded. THen I did it again with the replacement motor and it spun like the dickens. So i am going to replace the old motor and see what happens. We are thinking a bad ground but I can`t seem to find the other end of that burnt wire. Does it go back to the control module? IF so I can just run a new wire between the two. Make sense?
P.S. I cannot find a printable wiring diagram. everything I have is blurry and pretty much useless.

 

the fan's + wire (pin 1) goes to fuse 28 power via a violet wire... the fan's - wire (pin 2) goes to the fan power module's (FPM) pin 1A via a blue-black wire. internallly in the power module, pin 1A is wired to pin 6B (motor sense, goes to the ECC pin 19 via a pink wire), pin 1A is wired to the 'darlington power transistor' (think of this is a sort of really high speed relay, controlled by pin 4B (red-black to ECC pin 8), and it grounds the motor to pin 2A which is a black wire to ground (somewhere near the tranny hump under the console?), and its wired to a relay switch also to pin 2A (this acts like a bypass on the 'darlington power transistor').

 

Great, I'm glad the fuse did not blow when you grounded the blue wire.

Reading into pierce's explanation the A connector (two terminals) on the power box is what you are concerned with. The black wire is the ground for the fan and the blue wire (I understand this is the one with the burnt terminal, at the fan connector) leads to the fan. The black wire probably runs to a ground point on the transmission tunnel, but it's spliced with other black wires along the way.

I think that you should "go around" the burnt terminal on the fan connector using quick disconnect terminals or even a wire nut if that's what you are comfortable with. Should you ever want to replace the factory terminal itself, they pop out of the plastic connector housing, and volvo sells them with lengths of wire attached so you don't have to crimp terminals.

There are wiring diagrams available for download at volvowiringdiagrams.com. For your 92 they have a thirdparty drawing set that is very concise and easy to read. If you want more details, download the TP3905202 version of the 1994 book too. This is a factory manual and the ECC pages look like they match exactly the 92. I've printed from both of these to figure out what the power box does and the quality is ok.