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Has anyone had trouble/success getting the charge warning light working on the civic engine? I was trying to suss it out today - good job too as I eventually found a really embarrassing wiring error in my charging circuit which meant I was getting no charge (let's just say the main +ve charge lead from the alternator is black....and I leapt to the obvious wrong conclusion when hacking around with the engine loom some time ago - fortunately the engine is too kind to me as I don't appear to have a fried alternator!)
Anyway, voltage is now a healthy 14V when the engine is running, but no joy with the charge light. The hondata wiring diagram showed the charge light being sunk via the engine loom plug to the white/blue wire (alternator "L" I think). Now my loom plug did not have that connection present, but the alt "L" wire goes straight to the ecu (B18 I think). I have tried tapping directly into this wire to sink my charge light, but now the light goes off (wire sees 12V from the alternator) as soon as I turn the ignition on, before the engine is fired up... Anyone confirm if I'm trying the right thing - or have I actually damaged my alternator circuitry along the way?
Ta
Richard
I saw the Hondata diagram and noted the charge light wire, which I didn’t initially bother with when I was trying to start my engine. What I did discover, the moment I started my engine, is that the PRM ecu, in the oem installation, transmits the charge status to the OEM dashboard using the multiplex wire (along with revs, and engine temp).
I know this doesn’t provide an instant solution to your problems, but it did make me wonder if there’s a subtle difference to the UK ecu, and that the hondata wiring diagram isn’t entirely appropriate. As I’m using the Honda clocks I didn’t pursue my investigations any further.
John,
You're not wrong - in a number of areas (primarily O2 sensor) the hondat diagram is not correct. I was assuming the alternator "L" wire was the same between US/Uk engines but maybe not...
I planned from the outset on using the Rover clocks, thinking (wrongly!) that this would be an easier option. Not so! For any prospective Type-R builders out there - stick with the honda instruments I think. The dashboard mods are I imagine pretty straightforward (correct me if I'm wrong John?) and it seems the multiplex etc just works fine. Once I've messed around with new faces, pulse dividers to re-range the clocks etc etc and now the charge light, I'd have been better off with Honda.
I might have to rig up some kind of comparator circuit to a 12V reference to get my charge light working. Ah well - not essential for SVA at least!
Just to make you feel slightly better about the route you've taken.....
When using the civic clocks, you need: a pulse divider for the speedo; to offset the reistance of the fuel level sender; to cut the track to the brake fluid / handbrake warning light and solder in a wire. You also need to use a relay with the handbrake switch (it's not possible to cut the ground for the dash led).
On the plus side the honda dials I think look the part, and they aren't expensive - I've two (whilst moulding the dash the polyester resin partially melted the clear cover on my first unit), and the second fully functional unit cost me £26 (delivered) on ebay.
You could always sack off the charge light, and have a voltmeter.....though that's a bit cowboy!
Ah, that does cheer me up
Nothing is straightforward in this game eh? I've been through two sets of rover instruments myself after buggering gauges while changing needles. My local yard lets me rip them out for £10 so it's not too painful. They're easy to clock the odo too - mine now happily reads a grand total of 3 miles (and that has been done up on stands!).
I thought about the voltmeter option - quite good info but nowhere obvious to put it. It might be a later mod - a pod with volts and oil presure gauges somewhere.
Alternatively I reckon a zener diode and a few other bits and bobs and I should be able to rig something up to get the light working. In the meantime if I want to check the battery I can keep a laptop plugged in with K-Manager working its magic....
