Results 1 to 13 of 13

Thread: New guy asks question right off the bat - Gauges and Reverse lights

  1. #1
    Join Date
    Nov 2018
    Posts
    6

    New guy asks question right off the bat - Gauges and Reverse lights

    I tried looking up the questions regarding these issues I'm having, before posting...
    I just bought a beautiful 89 SC. 5 speed.
    I've got 3, small, but odd issues:
    - The headlight switch acts as a dimmer switch for the taillight when you turn the knob. I seen a member stated buying a new headlight switch. Just need to find one now.
    - The reverse lights have no power going to them.
    - All the gauges, with the exception of the tach, and boost seem to be off. The speedometer is a bit off too, but that's my least concern on the cluster. The temp gauge goes all over the place, as does oil pressure. I made a tighter and cleaner connection on the oil pressure sender. The fuel gauge is showing beyond full. I'm in the process now of pulling the cluster out and looking for any loose connections, not really sure where to look.
    Any pointers would be greatly appreciated.

  2. #2
    Join Date
    Dec 2007
    Location
    Salem OR
    Posts
    6,804
    Temp gauge fluctuation often means the push-on connector at the sender near the thermostat housing is loose and/or corroded. Clean both, then gently squeeze the connector so it grabs the terminal better. Don't ignore the cooling system...might be air that is causing such readings.

    The oil pressure gauge is more an idiot light than any kind of value-based pressure reference. The gauge only indicates some level of pressure, or not. On/off.

    About the headlight switch, don't ignore the turn signal/multi-function switch. If you replace it, be sure it's color coded to match what comes out.

    About where to look on the back of the cluster, there are two large connectors that need to be released when removing. I'd confirm those and their respective sockets are clean (no corrosion), and properly seated.

    Know that you may need to confirm the health of the multi-wire ignition switch located on the right side of the steering column, inside the dash. They tend to come apart w/age, leading to many otherwise confusing issues. Cost is low and recommend you replace if of unknown age.

    And finally, the age of these cars means that corrosion can lead to many, many problems. You need to find the time to inspect connectors (being careful to not break the keepers, as they are brittle now), and bulb s and their connectors. Replace bulbs if the connections on them are black or green.

  3. #3
    Join Date
    Nov 2018
    Posts
    6
    Awesome. Thanks a lot for the detailed reply.

    I was also given an electrical/vacuum manual with the vehicle. Do the wire colors change throughout the vehicle?
    For instance, the reverse lights at the connectors are black and purple. Are they black and purple all the way to the power distribution ?
    What throws me off is that the book shows the wire colors to be "BK/PK" (black and pink.)

  4. #4
    Join Date
    Jan 2010
    Location
    Bossier City, LA
    Posts
    2,245
    Quote Originally Posted by Mike86 View Post
    Awesome. Thanks a lot for the detailed reply.

    I was also given an electrical/vacuum manual with the vehicle. Do the wire colors change throughout the vehicle?
    For instance, the reverse lights at the connectors are black and purple. Are they black and purple all the way to the power distribution ?
    What throws me off is that the book shows the wire colors to be "BK/PK" (black and pink.)
    Unfortunately, and as you follow the wiring you discover, sometimes the color of the wire will change, depending on what else is connected to that particular wiring bundle.

    And they may have been made black and pink, but age faded to black and purple. Or just be a very dirty pink that looks purple.

    RwP

  5. #5
    Join Date
    Dec 2007
    Location
    Salem OR
    Posts
    6,804
    Quote Originally Posted by Mike86 View Post
    Do the wire colors change throughout the vehicle?
    Circuits can change colors depending on where you are on the circuit, which route in/out, based on what purpose etc.. Sometimes including one switch, sometimes more, sometimes a shared circuit, sometimes routed thru one or more controllers. The EVTM will reference up/downstream companion circuits, along with 'troubleshooting tips' that help you work the problem without too much tail-chasing.

    Hint - Ford loves to make or break circuits via grounds. SCs live and die on their grounds. Always confirm ground paths exist as designed, not corroded, and provide the proper resistance. If any doubt, replace. Remember corrosion can live inside a wire's sheath, and since electricity moves along the surface of a wire, don't assume a circuit is ok without testing and close examination.
    Last edited by KMT; 11-24-2018 at 04:21 PM.

  6. #6
    Join Date
    Nov 2018
    Posts
    6
    Thanks for the help guys, I do appreciate it.

  7. #7
    Join Date
    Oct 2005
    Posts
    2,296
    ................................
    Last edited by TSC89; 11-27-2018 at 06:17 PM.
    Jim, SCCoA Member#: 2789

    "cuz Jim has mad skillz, yo!" Melon.
    "You guys crack me up talking about nitrous when you don't even know if you can keep it together on gasoline." XR7 Dave
    "I didn't break it, I found it's weakness."

  8. #8
    Join Date
    Dec 2007
    Location
    Salem OR
    Posts
    6,804
    Quote Originally Posted by TSC89 View Post
    I would suggest getting a Thunderbird EVTM
    Quoting TG yet again, 'nobody reads the thread...'

    The OP already mentioned they have one.
    Last edited by KMT; 11-27-2018 at 03:25 PM.

  9. #9
    Join Date
    Oct 2005
    Posts
    2,296
    Quote Originally Posted by KMT View Post
    Quoting TG yet again, 'nobody reads the thread...'

    The OP already mentioned they have one.
    ....................
    Jim, SCCoA Member#: 2789

    "cuz Jim has mad skillz, yo!" Melon.
    "You guys crack me up talking about nitrous when you don't even know if you can keep it together on gasoline." XR7 Dave
    "I didn't break it, I found it's weakness."

  10. #10
    Join Date
    Nov 2018
    Posts
    6
    I do have one, but it may as well be in Chinese. Still trying to understand the orientation of things in there. It'd be excellent if it gave me a reference of where things were. Maybe it does but I'm not there yet. I'm doing what I can to understand it.


    If anyone is still reading this..

    I had a battery drain and hooked up my multimeter. Disconnected fuses until i found the culprit. I believe it was about 0.3 draw.
    Interior lights are sucking power, yet there are none on? How does that work?
    I'm guessing previous owner had known about this as the fuse was different than the rest. As of right now, the fuse is disconnected and I'm likely going to start pulling bulbs to see when the numbers drop. Is that the right idea?

    Funny how you start on one project and it becomes something completely different.

  11. #11
    Join Date
    Dec 2007
    Location
    Salem OR
    Posts
    6,804
    When chasing interior lights, don't overlook the pair underneath either side of the dash, the one inside the glovebox, and the one inside the center console. The mirror on my '90 has two bulbs with small rocker switches that point down, so it's easy to not know if they are lit in the daytime if the switches are left on, which overrides the door open switches.

    Be sure to also check the light under the hood...don't forget it will it will be lit if you have the hood open while checking drain at the battery. And finally there is a light inside the trunk. Pulling bulbs, as you noted, is a good step, when you can get to them.

    When pulling fuses, don't ignore the big ones in the Power Control Box next to the battery.

    So you know, there are harnesses under the carpet in several locations...sometimes they suffer if the carpet/insulation has been compromised.

    The EVTM has legends and troubleshooting flow explanations in the forward, 'How to use...' and 'Helpful Reminders' that should to help gain understanding. Wiring on an SC is intimidating, no doubt - the better acquainted you become with the EVTM, the less tail chasing you'll experience long term, steep learning curve and all that so pls. stick w/it - I'm sure you'll get the hang of it soon enuf.

    As for drain, I see a normal of 0.43mA - was 1A until I isolated a relay short in my sub amp wiring a few months back.
    Last edited by KMT; 11-27-2018 at 11:31 PM.

  12. #12
    Join Date
    Nov 2018
    Posts
    6
    Thanks again for the pointers, KMT. 👍


    Electrical is a pain. That's for sure.

  13. #13
    Join Date
    Nov 2018
    Posts
    6
    Reverse light figured out...

    Disconnected plug from the reverse switch on the transmission.
    Last edited by Mike86; 11-30-2018 at 09:49 PM.

Similar Threads

  1. New guy that was lost in the woodwork
    By Boosted91 in forum New SC Owner Forum
    Replies: 4
    Last Post: 02-02-2010, 12:25 PM
  2. say hello to the new guy!!!!!!
    By jaceqq in forum Non Technical Forum
    Replies: 5
    Last Post: 03-28-2003, 03:46 PM
  3. new sc owner has question on starting the sc'c
    By hockeydad2 in forum Technical Forum
    Replies: 11
    Last Post: 01-04-2003, 02:17 PM
  4. New guy w/ questions...
    By DJ SHO in forum Non Technical Forum
    Replies: 9
    Last Post: 07-25-2002, 04:01 PM
  5. "The New Guy"
    By hilldogsc in forum Super Coupe Club of Northern California
    Replies: 8
    Last Post: 08-25-2001, 12:01 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •