sierra3dr 49 Posted June 4 9 hours ago, MK5CortinaEstate said: The ballast wire is the resistor. Does it have a ballast inline of the cable? Quote Share this post Link to post Share on other sites
sheffieldcortinacentre 600 Posted June 4 Yep it looks like a thick grey cable taped to loom ( some replacements were blue) bit thinner than a HT lead but bigger than normal wire. On prefacelift MK3 it runs across bulkhead underneath heater box, facelift onwards & MK4/5/P100 on drivers inner wing except Mk5 2.3 & 82 2.0 ohc with electronic ignition. as the use full 12v rather than 9v that points version does. Quote Share this post Link to post Share on other sites
sierra3dr 49 Posted June 4 Here is how it is laid out on mine and I am on accuspark with a 12v coil. Trying to cast my memory back if I have detached the ballast wire under the tape near the bulk-head. In general,all are as follows.frrom the ignition switch it is yellow/black--->(after the bulk-head)Black---->grey ballast wire---->2xyellow/black. One of the yellow/black goes to the coil,and one goes to the starter Ballast wire.mp4 1 Quote Share this post Link to post Share on other sites
Heedwa 6 Posted June 4 49 minutes ago, sierra3dr said: Here is how it is laid out on mine and I am on accuspark with a 12v coil. Trying to cast my memory back if I have detached the ballast wire under the tape near the bulk-head. In general,all are as follows.frrom the ignition switch it is yellow/black--->(after the bulk-head)Black---->grey ballast wire---->2xyellow/black. One of the yellow/black goes to the coil,and one goes to the starter Ballast wire.mp4 Thank you! That's really helpful. Didn't get a chance to look today, bad weather. I'm pretty sure the resistor splits the same way on the mk3 too, with the yellow/black wires. Previous owner made a bit of a mess of the wiring so will have to have a good close look 1 Quote Share this post Link to post Share on other sites
sierra3dr 49 Posted June 5 Would there be a part number on the 9 volt coils,new one and the old one? Quote Share this post Link to post Share on other sites
Heedwa 6 Posted June 5 5 hours ago, sierra3dr said: Would there be a part number on the 9 volt coils,new one and the old one? I'll take a look. The old one is off the car so I can look at that one for you now. The new one I can check later when I get to the car. Can't remember seeing parts numbers but will have a look 1 Quote Share this post Link to post Share on other sites
sheffieldcortinacentre 600 Posted June 5 Depending on brand there should be, they usually say 12v or 9v or ballasted. 1 Quote Share this post Link to post Share on other sites
Heedwa 6 Posted June 5 (edited) Here are some pics which should give some info on the two coils. New one is the lucas label (coil is in the car) , old one is the black coil. Both are 12v as you can tell from the pics. Black coil came with the car and car ran fine with it on for a while. Edited June 5 by Heedwa 1 Quote Share this post Link to post Share on other sites
sheffieldcortinacentre 600 Posted June 5 Your Lucas one is for points ignition to be used with a ballast resistor ( as from factory). The black one is for use with electronic ignition ( no ballast resistor ) all 2.3 mk5's ( not MK4) & 82 2.0 mk5's, & most 83 onwards fords especially Sierra's,cvh escort/Orion/fiestas ,V6 Capri/Granada, all MK3 Granada, MK2 fiestas,MK3 transit (late mk2 transit). 1 Quote Share this post Link to post Share on other sites
Heedwa 6 Posted June 5 Guess I'll keep the Lucas one on then! The car has points ignition. It's funny though because it was running for a while with the black one on. Would that have caused any damage do you think? Quote Share this post Link to post Share on other sites
sierra3dr 49 Posted June 5 15 minutes ago, Heedwa said: Guess I'll keep the Lucas one on then! The car has points ignition. It's funny though because it was running for a while with the black one on. Would that have caused any damage do you think? If it is the same coil that has been on since day one it left the factory,I would say it has become damaged due to wear and tear. But generally,parts do age and become worn. Thanks for the part numbers 1 Quote Share this post Link to post Share on other sites
sheffieldcortinacentre 600 Posted June 5 With that coil it may have burnt the points due to constant 12v rather than 9v check to see if the contacts look bluey/ black or if one is loose/fallen off. 2 Quote Share this post Link to post Share on other sites
Heedwa 6 Posted June 5 I did have a look at the points, and changed them while I was at it, so it has new points now, and a new condenser. I located the ballast wire and did a test with the multi meter. Just want to check I did this correct: I disconnected the bullet at the coil end, turned the key to II, then grounded the black wire on the multi meter and placed the red wire from the multi meter to the male bullet connector on the ballast wire. I did the same on both ends. On the end nearest the coil I got a reading of over 12v, and then near the driver side I got a reading of zero vaults. If I did this correctly, does this mean the ballast wire is gone and I need to replace it? Thanks for all your help so far Quote Share this post Link to post Share on other sites
sierra3dr 49 Posted June 5 Have you bought the Cortina recently? Quote Share this post Link to post Share on other sites
sierra3dr 49 Posted June 5 10 minutes ago, Heedwa said: On the end nearest the coil I got a reading of over 12v, I think that is the temporary 12v for startup. Might be best testing when it is running to see if it drops to 9v Quote Share this post Link to post Share on other sites