| Author | Message | ||
     Edward Mckinley Experienced User Username: ed_mckinley Post Number: 32 Registered: 2-2013 |
Upon realizing that my auxiliary electric fans should not be constantly running on my 89 Corniche, I began to consult the manual, TSD 4701 section 30-3. If I remove the 10 amp fuse in fuse board 1, location B2, the fan stops, which according to the schematic is part of the sensing circuit although on my fuse board it's marked as indicators and does power them also. I tried swapping the relay with no success, and also tried disconnecting the wires on top of the thermostat housing with no success. The fans only run if the bonnet is closed, although I don't see that switch in the wiring diagram in 30–3. if anyone has any experience with this I would certainly appreciate some guidance . Thanks | ||
| Paul Yorke Grand Master Username: paul_yorke Post Number: 1683 Registered: 6-2006 |
Not near a wiring diagram but . . . Does your car have a pressure switch near the air con receiver dryer? Over pressure may bring the fans on. It's loom is also close to the left hand bonnet hinge . . . Could it be fouling / shorting there? | ||
| Edward Mckinley Experienced User Username: ed_mckinley Post Number: 33 Registered: 2-2013 |
If it is the part that I think, it's sitting in the upper left-hand corner behind the left side headlamps it has refrigerant hoses going to it and it has a green cap on it with two wires coming out. if I disconnect those two wires the fan continues to run regardless | ||
| Paul Yorke Grand Master Username: paul_yorke Post Number: 1684 Registered: 6-2006 |
With the bonnet open and closed. Any sign of chuffed wiring looms? Wondering if it's possible to swap the connectors bonnet light switch and that switch by mistake? Still not near a wiring diagram. | ||
| Christian S. Hansen Grand Master Username: enquiring_mind Post Number: 423 Registered: 4-2015 |
Paul...that's a brilliant idea provoked by the "red light" that the issue is affected by the condition of the bonnet...open versus closed...indicating that the problem is related to the bonnet position either touching, moving, or otherwise affecting the wiring for the fan...or not! Nevertheless a symptom that so "jumps out at you", that it screams "investigate further along that line." Don't we just hate these gremlins? shades of Omar's bad connection for his transmission...not the first thing to pop into one's mind to check!! | ||
| Edward Mckinley Experienced User Username: ed_mckinley Post Number: 34 Registered: 2-2013 |
I will check that today as a possible cause but I thought perhaps the fans only ran with the bonnet closed as a safety precaution? Also, the bonnet light does operate correctly | ||
| Paul Yorke Grand Master Username: paul_yorke Post Number: 1686 Registered: 6-2006 |
No. Fans are independent of bonnet possition. | ||
| Edward Mckinley Experienced User Username: ed_mckinley Post Number: 35 Registered: 2-2013 |
Found a nicked wire which was shorting out against the hinge when the bonnet closed. Easy repair and the fan is now working properly. Thanks for your all your help. On a separate note while I was troubleshooting it I managed to break the little switch for the bonnet lamp. The switch feels rather cheap, has anyone come up with something better as a replacement? The parts manual lists it as UD12195 | ||
| David Gore Moderator Username: david_gore Post Number: 2320 Registered: 4-2003 |
Edward, Do you have a mercury switch or a mechanical switch? Both types should be available from an electrical hobby supplier if you take the old switch to them for matching. I prefer the mercury switch for its simplicity and lack of moving parts. https://www.jaycar.com.au/mini-mercury-switch-spst/p/SM1044 David | ||
| Edward Mckinley Experienced User Username: ed_mckinley Post Number: 36 Registered: 2-2013 |
Mine is the mechanical type and mounted Low on the left-hand side hinge mechanism and attached with cable ties. I assume if you use this Mercury switch you are mounting it to the underside of the bonnet? | ||
| Paul Yorke Grand Master Username: paul_yorke Post Number: 1689 Registered: 6-2006 |
Great news on a strange fault. | ||
| Christian S. Hansen Grand Master Username: enquiring_mind Post Number: 428 Registered: 4-2015 |
Hey, Edward...I need that switch too, so be sure to post where you get a replacement and part #. The original as on my SRX2541 is mechanical with a plastic button that is pushed as the hinge closes. The underbonnet light is basically useless as compared to a quality torch(UK)/flashlight(US) but it is still nice when things work as they should! | ||
| David Gore Moderator Username: david_gore Post Number: 2324 Registered: 4-2003 |
Edward, Yes, it is mounted on the bonnet lid and will activate shortly after the bonnet is lifted. A simple rewiring is all that is needed to link the mercury switch to the original mechanical switch connections. I also suggest you replace the engine bay light with a LED unit[s] to give brighter and more effective illumination. The OEM lights are as effective as a candle in the wind IMHO. https://www.jaycar.com.au/products/outdoors-auto-products/outdoor-portable-lighting/12vdc-battery-lighting/c/801D My apologies for using local suppliers to illustrate the items I am referring to however similar suppliers should exist in the USA. David | ||
| Edward Mckinley Experienced User Username: ed_mckinley Post Number: 37 Registered: 2-2013 |
Here is the actual original equipment switch, sure beats $65.00 for it to come in a Bentley box http://www.ebay.com/itm/Bulgin-S621-Old-Fashioned-Door-Switch-Single-Pole-On-Off-OM527B-/251882077268?hash=item3aa5577c54:g:xpcAAOSwrklVBwt1 | ||
| Christian S. Hansen Grand Master Username: enquiring_mind Post Number: 438 Registered: 4-2015 |
Edward... Thank you for sharing that find. Now I can have a functional underbonnet light, too...and under $10US delivered!! | ||
| Mark Aldridge Grand Master Username: mark_aldridge Post Number: 373 Registered: 10-2008 |
Thanks Edward, just bought 2. Do you know the BULGIN part no. for the door switches ? Regards Mark | ||
| Edward Mckinley Experienced User Username: ed_mckinley Post Number: 38 Registered: 2-2013 |
I do not, but the Bulgin part number was molded on the switch itself so perhaps it is the same for the door, once you remove it |
