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T-Series ignition switch?

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WillR

WillR

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New owner of the 78 B That was stalling and backfiring. Had it running on Friday stayed close to home and good thing. Now when i turn the key ignition light comes on but starter wont come on. When key is all the way turned Then the interior lights lights come on bright. Im guessing something to do with the seat belt module. I can use a remote starter switch and its fine. Any ideas?
Will
 
The seatbelt module won't affect the starting circuit in a stock wired '78. The white/red wire from the ignition switch branches to two locations, the starter relay, and the seatbelt module.
Take a look at the wiring diagram for your car. Wiring diagrams are available at https://www.advanceautowire.com click on stock schematics.

Check the starter relay. You should have 12 volts going to the relay from the white/red wire when the ignition switch is in the start position. The brown wire should always supply power to the starter relay. The black wire should always be connected to a good ground. The white/brown wire should have 12 volts only when the ignition switch is in the start position.

Check the all the connections at the starter, make sure they are clean and securely connected.

What interior lights are you refering to? The only lights that should come on when the ignition switch is in the start position are the dash brake light, the ignition/alternator light, and the EGR light if fitted. The dash brake light and the EGR light get power from the white/red wire when the ignition switch is in the start postition. The igntion/alternator light turns on when the car is on and the alternator is not putting out enough amps. The alternator will not put out any amps if the motor is not running.

Can you push start the car?
 
i was unable to push start the car.<span style="font-style: italic">But i did use a remote starter switch and it started</span> both the dome light and two small lights in the heater switch area come on bright. i am unable to work on the car today, but i will have time to play with the wires tomorrow afternoon.
Thanks for the advice
 
Also, check/clean the connections at the 2 relays on the passenger side wing, near the fusebox.
 
Does the brake light on the console work? Is your car fitted with a service counter?

Has there been any work done around the console?
 
The Brake light does not come on, but i cant get the parking brake to work either. It does not look like any work has been done to the console. This may or not be related but turn signals do not work. Hazard work intermittently and only the right side. Seems like tomorrow will be wire day after class.
 
Time to get out the meter or test light and to make yourself a couple of enlarged copies of the wiring diagram for your car, one for reference and one to make notes on as you check the circuits. Look for pinched or chaffed wires. Make sure all the ground connections are clean and secure. Clean each connection and apply dielectric grease to prevent future corrosion.
Wiring diagrams are available at https://www.advanceautowire.com click on "stock schematics"

Start with the easily accessible areas, but be methodical.
Try unplugging the seatbelt module since a purple wire and a white/red wire connect to it to rule out any internal failure. Permanently disconnecting the seatbelt module should have no effect on any other circuit. The seatbelt module is located behind the console.
Make sure no white/red wires have been crossed with red/white wires.

For the parking brake, check section M in your Bentley manual. Make sure your rear brakes are properly adjusted, that the cable and moving parts aren't siezed, and the cable is properly adjusted.
 
Kimberly said:
For the parking brake, check section M in your Bentley manual. Make sure your rear brakes are properly adjusted, that the cable and moving parts aren't siezed, and the cable is properly adjusted.
Click to expand...

Do you mean to say that the parking brake mechanism itself may interrupt the ability to start the vehicle?
 
Dave Richards said:
Kimberly said:
For the parking brake, check section M in your Bentley manual. Make sure your rear brakes are properly adjusted, that the cable and moving parts aren't siezed, and the cable is properly adjusted.
Click to expand...

Do you mean to say that the parking brake mechanism itself may interrupt the ability to start the vehicle?
Click to expand...

No, WillR is having electrical problems. The brake light on the dash is suppose to come on if the ignition switch is in the start position. I was trying to determine what is working and what is not in order to help isolate the fault.
WillR said his parking brake is not working, a separate mechanical problem.
 
Kimberly said:
Dave Richards said:
Kimberly said:
For the parking brake, check section M in your Bentley manual. Make sure your rear brakes are properly adjusted, that the cable and moving parts aren't siezed, and the cable is properly adjusted.
Click to expand...

Do you mean to say that the parking brake mechanism itself may interrupt the ability to start the vehicle?
Click to expand...

No, WillR is having electrical problems. The brake light on the dash is suppose to come on if the ignition switch is in the start position. I was trying to determine what is working and what is not in order to help isolate the fault.
WillR said his parking brake is not working, a separate mechanical problem.
Click to expand...

Got it! Helped him along via phone today, he's at work tonight...he indicates the relay had power at the appropriate times. He's going to take <span style="text-decoration: underline">another</span> good look at the wires and connections at the starter.

He's got a blow up (and a color copy) of Advance's schematic.

It baffles me that the remote switch works, that would seem to indicate the relay or the connections are bad, but after a pretty good look the wires seem to be connected well.
 
I'd think if the remote switch energizes the starter and the key doesn't, either the iggy switch or relay are at fault.
 
What is bothering me is that the courtesy lamp comes on when the ignition switch is in the start position.
The courtesy light is suppose to have a constant power source from the purple circuit and a switched ground.

I'm am also puzzled as to why the illumination lamps (should be powered by the red/white wire circuit) for the heater controls come on when the ignition switch is in the start position. They should only come on when the headlight switch is closed.

Almost sounds like some crossed, shorted wires, or some sneaks caused by bad ground connections.
 
Doc: agreed

Kimberly: also agreed, Since so much work has been going on in the car and under the hood, shorted wires, or bad grounds are likely exacerbating the problem.

Time to patiently sort through both areas.
 
OK!! with a little patience we went through each wire and used the dielectric grease. The key is able to start the car!! I am guessing the relay was getting a bad connection. Also i took apart the hazard switch. completely corroded. i used some copper wire to test and the turn signals work. Need a new switch now. Thank you for all the advice. The wires seem to be an issue in need of time this summer.
 
If the corrosion isn't through the copper inside the switch (meaning if the little h piece of copper ain't broken), it can be cleaned & put back in service.
 
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