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Message |
    
Bill Coburn
Grand Master
Username: bill_coburn
Post Number: 253
Registered: 4-2003
| | Posted on Saturday, 11 September, 2004 - 22:03: |    |
Well I was complaining about slow wipers on the Spur but the recent rain seems to have helped there. But in the middle of the storm I found that on switching them on there was a very definite delay before they started This applies to all switch positions. Any advice?? |
whunter
Prolific User
Username: whunter
Post Number: 83
Registered: 10-2003
| | Posted on Sunday, 12 September, 2004 - 13:47: | |
Burnt relay points, bad ground, bad brushes in the motor, damaged wiper switch or Gremlins running about in your wiring.
Fresh out of Gremlin traps. :BIG GRIN:
Do you have a spare relay to swap in?
Check alternator output, precaution.
How many AMPS is the motor drawing?
Did you lubricate the pivots yet?
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Bill Coburn
Grand Master
Username: bill_coburn
Post Number: 263
Registered: 4-2003
| | Posted on Friday, 15 October, 2004 - 09:15: | |
Sorry I haven't replied and thanks for the advice. The lube in the wiper mechs did help thanks. Finally they stopped altogether so I pulled off the motor and it was perfect inside. Then I played thimble and pea with the three relays and everything started again! What is bloody annoying is that I replaced all three relays when I got the car having heard of the problem and clearly one of these have failed OR we have dirty contacts under them! I have the emery boards and will be getting into those dirty little holes today. Meanwhile I have bought yet another two relays - all the local mob had!!! Cheers |
Richard Treacy
Grand Master
Username: richard_treacy
Post Number: 393
Registered: 4-2003
| | Posted on Friday, 15 October, 2004 - 20:11: | |
Bill,
A few points on those relays.
1. The relay size and pin layout is generic and is used on many makes of car. For test purposes I bought a handfuly of generic relays at the supermarket for $3 each. They are functionally identical but in black plastic instead of metal. On two, I have made a hole in the top, inserted a rod and sealed it with flexible RTV. To plug the relay on test or otherwise, simply push the top of the rod. I keep one in the glovebox just in case the convoluted starter interlock chain fails at a remote place. I would rather replace the starter relay on the firewall and press the relay than undertake diagnostics in an emergency, but have never needed it yet. I'll post a picture of it in-situ for anyone interested.
I have half a dozen Bosch relays for permanent use, but at $18 each I prefer to do diagnostics with the cheapies and use a new Bosch one (Bosch part 0 332 204 122) once the problems are solved.
2. If you have no spare and suspect a relay, simply swap a pair around and see if the behaviour changes.
3. You can open the relays, Bosch or generic, to see the condition of the contacts or to replace the diode suppressor. Don't use abarasives on the plated plugs or sockets any more than absolutely necessary or they will corrode quickly.
All this, and I have never had a relay problem.
Incidentally, I have rewired my high beam circuit. With the lights off, the main beam still flashes on the stalk as it always did, but the high-low sequencing relay no longer toggles. With the headlamps on, the relay toggles with the stalk as before. Why ? In the city, I use the flasher as a coutesy at intersections as is the norm. Unmodified, you can never be sure normally when you illuminate the headlamps whether it will be high or low beam if you have used the flas in the meantime. On the highway and in tunnels, headlamps are compulsory at all times. On a sunny day, it is very difficult and distracting to squint at the high beam warning lamp. If you always turn the headlamps off on low beam, they now stay that way until you turn them on again regarless of how many times you have used the headlamp flash with the headlamps turned off. One wire and three 10 cent diodes did the trick. |
Richard Treacy
Grand Master
Username: richard_treacy
Post Number: 394
Registered: 4-2003
| | Posted on Friday, 15 October, 2004 - 20:37: | |
This is a test relay temporarily in position as an emergency start function. If you are in the bush or at the theatre alike and the car fails to start, a 10 second relay swap beats waiting for the NRMA or climbing around looking for engine running relays on the spot.... Push the red button and you're off. I hope I never need it.
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Richard Treacy
Grand Master
Username: richard_treacy
Post Number: 397
Registered: 4-2003
| | Posted on Friday, 15 October, 2004 - 22:38: | |
Here is a picture of a good used Bosch relay opened up. If the contacts are perfect like these, there is no benefit in replacing the relay. Only the freewheel diode (read suppressor) can fail with age if the contacts are good. I replaced the diode for good measure. The diodes cost a few cents: any 1N4000 series diode is fine. The lid snaps back on and you simply press the metal sides of the lid flat against a bench.
Bosch relays use a diode suppressor and are therefore polarity sensitive. Most other brands use a bipolar suppressor. Functionally, there is little benefit either way, but the Bosch ones are less flexible in their application.
Consequently, the coil pins, universally standardised as pins 85(-) and 85 (+) on all brands, may be swapped, and will withstand transients of reversed polarity on most other brands but not on Bosch relays. Note the additional protection diodes needed for the Bosch relays on the window lift modification. This is because of transients of reversed polarity inherent with such long power cables in that specific application.
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Richard Treacy
Grand Master
Username: richard_treacy
Post Number: 399
Registered: 4-2003
| | Posted on Friday, 15 October, 2004 - 23:26: | |
Correction: the standardised industry norm for coil pin nomenclature is 85(-) and 86 (+). It is clearly marked that way on the side or top of the lid of most relays. |
Bill Coburn
Grand Master
Username: bill_coburn
Post Number: 267
Registered: 4-2003
| | Posted on Tuesday, 19 October, 2004 - 18:23: | |
Richard
My sincere apologies. I had not noticed your posts. This has happened a number oif times where I have had replies but all I am looking for is the red 'NEW'. Let me read the above. |