JVY
Active Member
Hi,
after refitting my headlamps, I decided to give them a check and came across a slighlty curious problem:-
with the lightswitch on the dash truned to the headlights position, at the front of the car I got sidelights and outer headlamp dipped beam (all as expected). When I switched the main beam lever on the steering column up to the ON position, only the outer headlamp main beams came on (i.e. no inner headlamp main beam). So, I thought I have probably blown a fuse while I was welding. Sure enough, checking the fuses, I found the one that feeds the inner main beam headlamps was open circuit. I replaced the fuse an did my test again.
This time, with headlight switch on the dash to headlights, I got the same results befoore (dipped beam on the outer headlamps as expected). However, flicking the the main beam lever up to ON position, I got no beam beam on any of the x4 headlamps! When I pull the main beam lever into "flash" position, all x4 main beams do flash on as expected.
Had a quick look at the wiring in dash/headlamps and all appears to be standard as per the Rover wiring diagram. After a bit of head-scratching and trying a few different things, I found that I could get everyting to work as expected by partially removing the inner main beam fuse! Basically, I just pulled the 32mm fuse out of it's lower clip and left it so it was just touching the bottom fuseholder clip but not actually clipped in. With the fuse like this, I can switch the main beam on as expected on all x4 headlamps by putting the steering colum lever up in to the ON position.
The only theory I can come up with is that the contacts in the steering lever switch have "carboned up". From the above, the switch will happily switch only the x2 50W outer main beams on. However, with the inner main beam fuse fitted, another x2 75W lamps are added to the circuit. This gives a total main beam power of 250W at a current of about 21A. I am wondering if the high current surge or arcing through the main beam switch is heating up the carbon on the contacts and ausing it to open circuit. Can I strip the main beam switch on the steering column to look at or clean up the contacts?
Has anyone seen anyhting like this before or do you maybe have any other ideas?
If I can't clean up the contacts I am thinking that I will have to try to obtain a new known good switch or maybe look at fitting a relay to switch the main beams?? 21 Amps does seem like a lot of current for a small switch that is quite frequently used.
after refitting my headlamps, I decided to give them a check and came across a slighlty curious problem:-
with the lightswitch on the dash truned to the headlights position, at the front of the car I got sidelights and outer headlamp dipped beam (all as expected). When I switched the main beam lever on the steering column up to the ON position, only the outer headlamp main beams came on (i.e. no inner headlamp main beam). So, I thought I have probably blown a fuse while I was welding. Sure enough, checking the fuses, I found the one that feeds the inner main beam headlamps was open circuit. I replaced the fuse an did my test again.
This time, with headlight switch on the dash to headlights, I got the same results befoore (dipped beam on the outer headlamps as expected). However, flicking the the main beam lever up to ON position, I got no beam beam on any of the x4 headlamps! When I pull the main beam lever into "flash" position, all x4 main beams do flash on as expected.
Had a quick look at the wiring in dash/headlamps and all appears to be standard as per the Rover wiring diagram. After a bit of head-scratching and trying a few different things, I found that I could get everyting to work as expected by partially removing the inner main beam fuse! Basically, I just pulled the 32mm fuse out of it's lower clip and left it so it was just touching the bottom fuseholder clip but not actually clipped in. With the fuse like this, I can switch the main beam on as expected on all x4 headlamps by putting the steering colum lever up in to the ON position.
The only theory I can come up with is that the contacts in the steering lever switch have "carboned up". From the above, the switch will happily switch only the x2 50W outer main beams on. However, with the inner main beam fuse fitted, another x2 75W lamps are added to the circuit. This gives a total main beam power of 250W at a current of about 21A. I am wondering if the high current surge or arcing through the main beam switch is heating up the carbon on the contacts and ausing it to open circuit. Can I strip the main beam switch on the steering column to look at or clean up the contacts?
Has anyone seen anyhting like this before or do you maybe have any other ideas?
If I can't clean up the contacts I am thinking that I will have to try to obtain a new known good switch or maybe look at fitting a relay to switch the main beams?? 21 Amps does seem like a lot of current for a small switch that is quite frequently used.