My 1998 XK8 has very low air flow from all of the vents. It sounds like the fan is blowing hard, but very weak flow. Pushing the various flow selection buttons and recirc button sometimes seems to have some very small effect, but not much. The air that comes out seems to be the called for temperature, hot or cold, just not much of it. I am having a hard time finding any information on how the ducts are laid out and function with the various selection options. Any information or guidance would be appreciated. It would be nice to get out of the car on a summer day without dripping sweat.

 

I'll bet ONE fan is blowing hard. (the other is likely DEAD)

 

I don't know how the ducting is set up, but wouldn't air be coming out from somewhere with one fan blowing if everything else was OK? I see the fan on the passenger side (RH), but haven't looked for another fan. I will get into it and see if that fan is running.

 

The fans 'blow' together and come out the vents. When one stops, the other tends to blow the air out the other fan housing.(not the vents)

 

I can find information on the RH fan, but very little on the LH fan. I think I can see it but don't have anything disassembled at the moment. I ran the actuator check by holding the Auto and Recirc buttons while turning on the ignition and none of the displays indicated a problem. I could hear actuators cycling through their tests, but don't know if they were actually working correctly. Also the error code only showed 23 which says it could be caused by cold weather. It was cold enough last winter to set the code. I cleared it and it didn't come back. Having done that, when the fan speed is on high the vents now blow at what I would consider to be a medium low speed airflow, but at least it is something and much better than it was. It would be nice to know what changed by running the diagnostics. As long as I get some airflow I'm inclined to let it ride for now. My experience is 24 year old plastic pieces tend to be brittle and break easily taking things apart and putting them back together. I've replaced some parts behind the dash, the starter, water pump, and power steering pump so I'm not afraid to tackle it if I have to, but may hold off for now.

Thanks for the response. I didn't know it had two cabin fans.

 

Tip for this: each fan has its own fuse. Disconnect these fuses in turn to figure out which fan (or both) still work.

Other tip is to go and pop the center (face?) trim, then remove a couple of screws to remove the vent. Once the face flap is open, there is a (mirror-assisted) view of the heater core and A/C evap.

eBay sellers for these used parts sometimes post great pictures. Worth a look.

Best of luck, keep us posted.

 

I found the drivers side blower is not working. The recirc door will open and close and air blows out of it from the passenger side fan when it is running as I was told it would. The fuses are good. I found another thread that said the blower relays are tucked above the plastic floor vent somewhere. No luck finding them yet on a quick look. I'm gathering wiring diagrams etc to get more serious about the troubleshooting. From the diagrams I have it looks like the power transistor is inside the blower assy. I can't find any information on how to remove the driver side (LH) blower assy. I have the lower bolster and a metal cross member removed so I can see the bottom of the assy and what looks like a couple of bolts at the top front, but no idea at this point what else is involved in getting it out. I did see a couple of blowers on EBay.

 

This is sometimes referred to as the ballast. You can normally see it on eBay pictures. It is external, it screws on to the duct. Given access, you could double check they are identical side to side and try a swap to confirm diagnostic. As you already found out, the passenger side setup seems much more accessible than the driver side.

Best of luck, keep us posted.

 

Good news and bad news. Good news, the motor isn't bad. The bad news, I found a problem with the wire from the 20 A blower motor fuse to the blower motor relay socket. Both sides of the fuse have 12V, the relay base has 0 V. I jumpered power from the RH to the LH relay socket and the LH fan ran. The diagrams I have show the wire coming out of the fuse panel connector FC6-2 to connector AC16-3 to the relay socket. So far I have not identified FC6 or located AC16. The manual location for AC16 says "left hand A post connector mounting bracket / A post trim" I can't find any information on removing the fuse panel or the trim piece surrounding it. Any info would be great. I will keep contorting under the dash in the meantime trying to track the wire.

 

I located connector AC16 that the power wire runs through mounted in front of the hood release lever. With the connector apart the section of wire from the fuse block to the connector checked OK, and the section of wire from the connector to the relay base checked OK, but when the connector was plugged back together there was high resistance from the fuse to the relay base. I could not extract the pin or the socket from the connector so I tried cleaning them the best I could with no help. I found tugging and pushing on the wires would on rare occasion complete continuity, but only long enough to blip my meter reading. I finally cut the wires on both side of the connector and crimped them to an insulated spade mating pair to reconnect the wires. The fan now runs. The mounting clips have a dimple that engages a lip on whatever mounts to them so it makes it a little harder to remove things from the clips. I tried a small screw driver in the slot in front of the clip to see if it would disengage, but not much help. I think just pulling harder finally removed them from the clips. Location pictures below.

 

2000 XK8 convertible. I have the same issue as the OP. I'm on a road trip and don't have my electrical diagrams with me. Can someone please tell me which fuses are for the fans so I can check them? Thanks

 

They are 20A yellow fuses - both number 11 - in the fascia fuse boxes, accessible with the relevant door open, one on the passenger side and the other on the driver side.

 

if your fuses turn out to be OK, then just one bad fan will cause the air flow to be pitiful on both sides. If you can get down low enough (ouch) you
can hear which fan is still working.

Z

 

Thanks guys! I found the passenger side fuse blown. I replaced it but still no air flow from that side. I pulled the fuse from the driver's side to make sure it was the fan that was blowing. It is. So I'll probably need a new (used?) pass side fan. That will have to wait until we are home, in a few days. My poor wife will have to suffer a while longer. Fortunately the heat wave seems to be abating.

Bill

 

I have finally got around to troubleshooting my a/c problems. To recap, on a trip in June during a heat wave, a/c air flow from the vents was inadequate. The RH fan was not functioning. I replaced the fuse and the fan still did not work.

Troubleshooting so far:
1. Discovered the fuse (#11, pass side fuse panel) blown again
2. Removed fuse and checked the downstream side of the fuse slot - hard ground
3. Removed glovebox and other bits for access and started working along the wires. The hard ground persisted and was found to be between the fuse panel connector (FC21) and the fan relay.
4. In the process of investigating, I discovered a bare wire at connector AC15, at the facia bottom mounting bracket RH. see photo 1. The bare wire was the black/white wire that supplies power to the all the temperature sensors and vent position sensing potentiometers in the a/c system. The insulation had been melted off.
5. I traced this wire as much as possible. The wire was also bare at the connection to the a/c module (AC4). See photo 2.Obviously this wire was passing too much current to something.
6. I looked at the aspirator assembly. Some previous owner had replaced the wires to the assembly! New, larger gauge wires were spliced in and then wrapped with tape. The remaining small bit of the black/wire looked a bit melty. I could only examine the black/white wires for the RH and LH fans pots, the other components are still inaccessible.
7. The in-car temperature sensor measures 1.8k ohms at 70F. I don't know if this is good or bad.
8. After all this troubleshooting, the hard ground at the fuse panel is gone. Maybe wiggling the wires did something, or maybe disconnecting the aspirator assembly did something. I don't see how the two circuits can be connected, except by physical proximity in the harness.
9. I replaced the fuse and now the RH side fan blows like crazy.
10. The a/c system is showing codes 11, 32, and 42. 11 is because the aspirator is disconnected.

That's all I have time for today. Clearly I will need to replace the bare wire. Does anyone have any suggestions about where to go from here? What is the normal resistance of a temperature sensor?

Thanks all!

Bill


photo 2, bare wire at connector AC4


Photo 1 - bare wire at connector AC15