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Topic: Need a wiring diagram for the ignition harness (Read 3757 times) previous topic - next topic

Need a wiring diagram for the ignition harness

I'm hooking up a remote start/remote lock for my 88 cougar with a 3.8. I'm doing a head gasket replacement, and decided I might as well do this while I'm at it, but I've run into a problem. When I hit the unlock/lock/trunk button the fuel pump kicks on for a second, thus the need for the diagram. I already went over the wiring guide given with the remote, and I've got it hooked up properly according to them, so either something is wrong, or this is a feature that I didn't know about.

Need a wiring diagram for the ignition harness

Reply #1 –
Found this on CoolCats.com

When you turn the ignition key forward ('ON') but do not fully start the car, a signal is sent from the ignition switch to fuel pump relay in the trunk, then to the inertia switch, then to the fuel pump in the tank (or on the framerail, depending on your model year). The fuel pump will audibly hum for a second or two in order to prime the fuel system and build up pressure.

There could possibly be a backfeed of current going to the "ON" position of the ignition switch with the remote starter feature wired up. Check the ignition switch to see if it is worn out or has sticky contacts that may arc between "ON' and "Start".

I could tell you a lot more if I seen the wiring circuits for the remote starter system itself and a description of where you made all of your connections.

Need a wiring diagram for the ignition harness

Reply #2 –
Typical Ford Fuel Pump wiring 88-91

Need a wiring diagram for the ignition harness

Reply #3 –

Need a wiring diagram for the ignition harness

Reply #4 –
Do the lights flash to confirm the action when you press a button? The reason I ask is because I recently had a problem with my fuel pump coming on when I turned the lights on. Turned out to be a bad ground for me. Good luck.
1986 Mercury Cougar - 2.3T/T5 swap, TC brakes and suspension and rearend, 3" exhaust, 255 lph fuel pump, Stinger BOV, Gillis MBC @ 18 psi
2003 Chevy Suburban Z71 - Daily driver
2015 Chevy Volt - Wife's daily driver

Need a wiring diagram for the ignition harness

Reply #5 –
Watchdevil, you are awesome. This is the guide that they emailed to me:
Function    Equipped    Type              
PASSIVE ANTI-THEFT     NO    -       
   
Wire/Function    Colour    Location/Description    Polarity    
   
12 VOLTS     Yellow    Ignition harness    +    
   
IGNITION     Red/green    Ignition harness    +    
   
ACCESSORY     Gray/yellow    Ignition harness    +    
   
STARTER     Red/blue    Ignition harness    +    
   
KEY SENSE     Black/pink    Ignition harness    -    
   
TACH SIGNAL    Green/yellow    At coil on engine    AC    
   
LOCK     Pink/yellow    In driver's kickpanel    Rev Pol    
 
   
UNLOCK     Pink/green    In driver's kickpanel    Rev Pol    
 
   
DISARM    Green/purple    In driver's kickpanel    -    
   
DOMELIGHT / ALL DOORS    Black/blue    At courtesy light under dash    -    
   
TRUNK PIN     Brown/white    At light in trunk    -    
   
TRUNK RELEASE     Manual release          
 
   
BRAKE SWITCH     Green    At switch above brake pedal    +    
   
PARKING LIGHTS     Brown    At light switch harness    +    
   
HORN           Green/red    At steering column    -

The lights do flash as a confirmation for it locking/unlocking. Which ground was causing your problem?

Need a wiring diagram for the ignition harness

Reply #6 –
The ground that was causing the issue was the one that bolts to the frame of the dash.  I would check to make sure it has a good connection.  Also one of the wires from that ground (it branches off into about 5 wires) goes off toward the steering column where it has a connector.  That needs to be hooked up also. 

Good luck, I know how frustrating electrical issues can be.
1986 Mercury Cougar - 2.3T/T5 swap, TC brakes and suspension and rearend, 3" exhaust, 255 lph fuel pump, Stinger BOV, Gillis MBC @ 18 psi
2003 Chevy Suburban Z71 - Daily driver
2015 Chevy Volt - Wife's daily driver

Need a wiring diagram for the ignition harness

Reply #7 –
Quote from: Loaded87IROC;322341
The ground that was causing the issue was the one that bolts to the frame of the dash.  I would check to make sure it has a good connection.  Also one of the wires from that ground (it branches off into about 5 wires) goes off toward the steering column where it has a connector.  That needs to be hooked up also. 

Good luck, I know how frustrating electrical issues can be.


Yes bad ground will cause backfeed on many circuits and cause nasty things to happen.

I looked over the wiring descriptions you provided and they all look right. I installed a remote door lock system on my Bird and most of these are familiar wire colors that I tapped into. So I would check grounds because the only way the door lock circuit could affect the fuel pump circuit is if somewhere there share a ground connection that is loose and the electricity choosed the path of least resistance through the ground wire going to the fuel pump relay or pump itself. Remember, the wiring for the fuel pump and power door locks travel from the driver's kick panel down the left side of the car. something right now is telling me that you should check the kick panel area for a loose ground wire. If it was not so late and dark I would look at my own car and take a quick look to see if there is a ground because there is no carpet or interior panels installed at this point. And I made several connections at the kick panel wiring to tap into the door lock/unlock wiring and the brown wire that illuminates the parking lamps and taillamps when I use the remote buttons.

So in short, check the entire kick panel area for a loose ground. Also as stated before, there is a ground on the steering column near the wiper switch and ground wires on the lower back of the dash frame behind the radio cavity in front of the floor vents.

Need a wiring diagram for the ignition harness

Reply #8 –
a single point of grounding is the transmission hump behind the ashtray.

search recent threads started by "joefriday" this year where he illustrated the ground point via a quick picture.

Im just commenting on gound locations,, havent had time to absorb your symptom and compare it to likley faults.

Need a wiring diagram for the ignition harness

Reply #9 –
I'll go over all the grounds I can find this weekend, I'm planning on having the head gaskets done this weekend also. After doing some more searching on the boards I found a post by Thunder Chicken, describing how he rewired his ignition. I'm planning on hooking up an aux fuse panel like he did, and starting with the remote start to remove any risk of burning out the switch.

Need a wiring diagram for the ignition harness

Reply #10 –
For anyone that was curious, it was something in the remote starter. I installed the aux fuse box, and it was still priming the pump when I locked or unlocked. I disconnected the wire connecting the remote starter to the fuel pump, and no more spitting gas. I should be able to fix it by installing a relay, I just need to figure out what to use as an activating wire for it.