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Topic: Lost cruise after 5.0 swap - 88 TC (Read 2831 times) previous topic - next topic

Lost cruise after 5.0 swap - 88 TC

ok, so the cruise in my 88 TC worked perfect when i got the car but i quickly dove into my 5.0 swap.  Then, 2 years later, i finally got the mustang cruise cable on the car...  but the cruise doesn't work.

Those of you who did this swap, did you have to do anything to get the cruise to work?  Does the computer have anything to do with this system?

Also, does the wiring for the cruise run through one or both of the circular plugs at the firewall (drivers side, engine compartment)?  Cause I repinned some things and added some things there to get some guages working, etc... maybe I screwed up something with the cruise?

What could be some of my problems, how can I troubleshoot?  And...I see "to speed control" on my wiring diagrams...  does that have anything to do with the cruise or does that refer to something like the speed sensor in the transmission?
1988 Thunderbird Turbo Coupe
'89 5.0 w/ ported intakes, Mallory Adjustable FPR, BBK shorties and H with 2.5" Flows, 130 amp 3G, 89 Mustang comp/wiring, Aluminum radiator w/ elec fan, T5 trans, King Cobra clutch, 3.55 gears, 13" Cobra brakes (front), Wilwood prop valve, Mustang A-arms, Front Coil-overs, MM CC plates, Silver 17x9 R's, 03 Cobra IRS, Aluminum DS, 2002 Mustang dash/console etc..., custom leather seats

Lost cruise after 5.0 swap - 88 TC

Reply #1 –
Mine worked when I changed the cable, so I don't think the firewall plugs have any connections for the cruse. Unlike the LSC, it's definatly a stand alone system, and not intergrated into the EEC. Possibly you just have bad buttons at this point, they are known for failure. I'll look at the EVTM later tonight or tomrrow.

Lost cruise after 5.0 swap - 88 TC

Reply #2 –
ok, thanks!  It's just weird cause the buttons and EVERYTHING worked perfect (never a glitch) before the swap...  so, is there a way I can test the buttons?
1988 Thunderbird Turbo Coupe
'89 5.0 w/ ported intakes, Mallory Adjustable FPR, BBK shorties and H with 2.5" Flows, 130 amp 3G, 89 Mustang comp/wiring, Aluminum radiator w/ elec fan, T5 trans, King Cobra clutch, 3.55 gears, 13" Cobra brakes (front), Wilwood prop valve, Mustang A-arms, Front Coil-overs, MM CC plates, Silver 17x9 R's, 03 Cobra IRS, Aluminum DS, 2002 Mustang dash/console etc..., custom leather seats

Lost cruise after 5.0 swap - 88 TC

Reply #3 –
To check the steering wheel buttons and contact assembly you can measure the blue/black wire at the amplifier(inside on the firewall above your left foot, or on the wire from the contact assembly). From ground pressing the ON button should give 12v(likely only while the button is depressed). Pressing the OFF button grounds the circuit, so it should read near zero ohms. Coast should read 120 ohms set/accel 680, and resume 2200...

Also is/was yout car a 5speed??? There is a connection to the clutch pedal assembly, If you've swapped to a Mustang clutch pedal(given) that's likely your problem. Circuit consists of a lt/green wire from the muliti-function sw, to the pedal and on to the amplifier. Jumpering the sw would restore oper, but system would not cut off by depressing the clutch.

Lost cruise after 5.0 swap - 88 TC

Reply #4 –
Thanks TurboCoupe50, I really appreciate the help!

Just to clarify:

Test the Blue/Black wire by hitting it with my multi-meter and grounding the other side of the meter to a chassis ground, then depress the button...obviously.  But then, the other buttons...  Am I testing the resistence of the circuit to a chassis ground also?  Meaning, test them the same way I did the blue/black wire, but with my multi-meter on ohms?

And yes, my car was a 5 speed.  I swapped in an 89 mustang pedal assembly.  I thought of that switch too, but only since I've been away from my car - never had  chance to check it out.  So it could even be that the switch is bad, maybe it's not even connected, and maybe it's out of adjustment (I'm assuming you can adjust it like the brake light switch).  Also, do you know if the switches are the same between the cars, or do I need the TC switch to work with the cruise circuit?
1988 Thunderbird Turbo Coupe
'89 5.0 w/ ported intakes, Mallory Adjustable FPR, BBK shorties and H with 2.5" Flows, 130 amp 3G, 89 Mustang comp/wiring, Aluminum radiator w/ elec fan, T5 trans, King Cobra clutch, 3.55 gears, 13" Cobra brakes (front), Wilwood prop valve, Mustang A-arms, Front Coil-overs, MM CC plates, Silver 17x9 R's, 03 Cobra IRS, Aluminum DS, 2002 Mustang dash/console etc..., custom leather seats

Lost cruise after 5.0 swap - 88 TC

Reply #5 –
You got it... Ohms with neg lead grounded for the buttons other than on...

Any switch that physically fits would work, just a open or closed circuit... Not sure if the TC sw would fit the Stang pedal assly.

Lost cruise after 5.0 swap - 88 TC

Reply #6 –
Ok, so I checked this stuff out (except for the clutch switch).  I got 12v from the On button, ground/0 ohms from the Off switch, but I can't really get any readings from the right three buttons...  So how can I service these buttons?  Any help would be great, I have to drive the car 2000 miles in about 24 hours (leaving sometime tuesday night or wednesday morning....)  Thanks!
1988 Thunderbird Turbo Coupe
'89 5.0 w/ ported intakes, Mallory Adjustable FPR, BBK shorties and H with 2.5" Flows, 130 amp 3G, 89 Mustang comp/wiring, Aluminum radiator w/ elec fan, T5 trans, King Cobra clutch, 3.55 gears, 13" Cobra brakes (front), Wilwood prop valve, Mustang A-arms, Front Coil-overs, MM CC plates, Silver 17x9 R's, 03 Cobra IRS, Aluminum DS, 2002 Mustang dash/console etc..., custom leather seats

Lost cruise after 5.0 swap - 88 TC

Reply #7 –
I'd be checking the clutch s/w first, since you switched clutch pedal assemblys I'm betting thats's your problem...

Lost cruise after 5.0 swap - 88 TC

Reply #8 –
Well, just checked the clutch switch, it's fine.  Shows about 0 ohms when the clutch is pushed to the floor.  I'm thinking since the on and off work and the other 3 on the other side don't, the contacts are bad.  I can't pull the wheel before leaving in about 3 hours, so just before I leave, I'm gonna spray some WD40 in there from the front.  I've seen this fix up a bad multi-function switch, so maybe...
1988 Thunderbird Turbo Coupe
'89 5.0 w/ ported intakes, Mallory Adjustable FPR, BBK shorties and H with 2.5" Flows, 130 amp 3G, 89 Mustang comp/wiring, Aluminum radiator w/ elec fan, T5 trans, King Cobra clutch, 3.55 gears, 13" Cobra brakes (front), Wilwood prop valve, Mustang A-arms, Front Coil-overs, MM CC plates, Silver 17x9 R's, 03 Cobra IRS, Aluminum DS, 2002 Mustang dash/console etc..., custom leather seats

Lost cruise after 5.0 swap - 88 TC

Reply #9 –
Oh Oh I got this one, swap back to the 2.3T!

;)
93 Festiva L, 193k miles, BP+T/G25MR swap, T3 50trim .48/.42, SRT FMIC, Capri electronics/Rocketchip, 2.5" exhaust
bests: ET 12.86, MPH 110.25, 1.92 short
02 Subaru Impreza WRX, 129k miles
97 Subaru Impreza Outback Sport, 236k miles

Lost cruise after 5.0 swap - 88 TC

Reply #10 –
Hahahaha, yeah, well.  I sometimes wish I stayed cause the 2.3T was pretty cool and now rare, but I will never deny that I like the 5.0 WAY better and it was a really fun swap!
1988 Thunderbird Turbo Coupe
'89 5.0 w/ ported intakes, Mallory Adjustable FPR, BBK shorties and H with 2.5" Flows, 130 amp 3G, 89 Mustang comp/wiring, Aluminum radiator w/ elec fan, T5 trans, King Cobra clutch, 3.55 gears, 13" Cobra brakes (front), Wilwood prop valve, Mustang A-arms, Front Coil-overs, MM CC plates, Silver 17x9 R's, 03 Cobra IRS, Aluminum DS, 2002 Mustang dash/console etc..., custom leather seats
 

Lost cruise after 5.0 swap - 88 TC

Reply #11 –
Quote from: bhazard
Oh Oh I got this one, swap back to the 2.3T!

;)


Some of us don't want HALF motors in our cars... Since I did mine back in '99, I've never regretted my swap... Anyway I've had 4/5 speed hot rods for the last 35 years, Time for a automatic...

Automatic TC's suck!!!

booksix..

Per EVTM the clutch switch is open when the clutch is depressed and closed (0 ohms) engaged...