Help With 92-93 Stereo / Climate Control VF Display Dimmer
#11
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Just a couple more notes... SSEiguy and I struggled with this one earlier:
http://www.bonnevilleclub.com/forum/...384&highlight=
It only affects the electronic climate controls because the manual climate controls don't have a VF display.
If you look at the troubleshooting areas:
1. The grey wire provides the rheostat signal (0-12V, dim to bright)
2. The green wire provides the headlamps on signal (0 or 12V, depending on headlamps on or off)
3. The purple and white wire provides a unique VF display dimmer signal (12V to 10V, as the rheostat is rotated from dim to bright)
Notice that a 12V signal applied to the purple'white wire will make the VF display turn completely off! I've tried it. The climate control is expecting the pulse-width modulated signal.
However, in 94, they changed the radio display from VF to a back-lit LCD display, but it appears that the climate control didn't change. Or did it? Is the climate control dimmer now self-contained, or is it simply wired differently?
I am working on getting the 94 wiring diagram, and also checking the part numbers on the 93 and 94 climate controls to see if they match.
http://www.bonnevilleclub.com/forum/...384&highlight=
It only affects the electronic climate controls because the manual climate controls don't have a VF display.
If you look at the troubleshooting areas:
1. The grey wire provides the rheostat signal (0-12V, dim to bright)
2. The green wire provides the headlamps on signal (0 or 12V, depending on headlamps on or off)
3. The purple and white wire provides a unique VF display dimmer signal (12V to 10V, as the rheostat is rotated from dim to bright)
Notice that a 12V signal applied to the purple'white wire will make the VF display turn completely off! I've tried it. The climate control is expecting the pulse-width modulated signal.
However, in 94, they changed the radio display from VF to a back-lit LCD display, but it appears that the climate control didn't change. Or did it? Is the climate control dimmer now self-contained, or is it simply wired differently?
I am working on getting the 94 wiring diagram, and also checking the part numbers on the 93 and 94 climate controls to see if they match.
#13
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I now have the 93 and 94 electrical service manuals. The infamous purple and white wire in pin No. 2 disappears in the 94 model! In its place is a yellow wire in pin No. 10. Pins 4 and 5 switch places.
I am going to try to wire in the "headlamps on" signal to my climate control at pin 10. If I don't get a VF display response, I will replace my climate control with a 94 model.
I'll keep you posted (if anyone cares!
)
I am going to try to wire in the "headlamps on" signal to my climate control at pin 10. If I don't get a VF display response, I will replace my climate control with a 94 model.
I'll keep you posted (if anyone cares!
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#14
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Originally Posted by fuddyduddy121
However, in 94, they changed the radio display from VF to a back-lit LCD display, but it appears that the climate control didn't change. Or did it?
I _love_ the dashboard display in the '93, because the contrasting color of the VF displays really makes them stand out. I _always_ get oohs and aahs from people who get into the car for the first time at night. (Almost everyone immediately says that it looks like an airplane cockpit.) I have yet to find a car with a nighttime dash display that'* cooler than this one.
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Originally Posted by acg_ssei
Originally Posted by fuddyduddy121
However, in 94, they changed the radio display from VF to a back-lit LCD display, but it appears that the climate control didn't change. Or did it?
I _love_ the dashboard display in the '93, because the contrasting color of the VF displays really makes them stand out. I _always_ get oohs and aahs from people who get into the car for the first time at night. (Almost everyone immediately says that it looks like an airplane cockpit.) I have yet to find a car with a nighttime dash display that'* cooler than this one.
#16
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Yeah, in 94 the radio became all red. Then in 2000 the Bonneville lost the remaining VF displays on the compass, DIC, and climate control.
I like the VF displays.
I like the VF displays.
#18
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I tried wiring the "headlamps on" signal to pin 10 of the existing climate control to no avail. At that point I ordered a 1994 control head.
I installed it today, and Voila! The dimming capability is back. I wired the existing climate control harness to accept a 1994 control head, which has its own VF dimming capability, yet would still work with the existing HVAC programmer. In addition to the pin 10 wire, pins 4 and 5 had to be reversed.
Here is some part info that I dug up while doing the research:
HVAC control heads:
92, 93 - 16160288
94 - 16201124
95-99 - 16220102
HVAC programmers:
92 - 16183308 or 16183312
93 - 16190465
94 - 16197178
95-99 - 16218972
I'll have to post a techinfo procedure for the complete installation of a newer stereo into the 92-93 models. I will take some pictures soon.
This should close this thread out, finally.
I installed it today, and Voila! The dimming capability is back. I wired the existing climate control harness to accept a 1994 control head, which has its own VF dimming capability, yet would still work with the existing HVAC programmer. In addition to the pin 10 wire, pins 4 and 5 had to be reversed.
Here is some part info that I dug up while doing the research:
HVAC control heads:
92, 93 - 16160288
94 - 16201124
95-99 - 16220102
HVAC programmers:
92 - 16183308 or 16183312
93 - 16190465
94 - 16197178
95-99 - 16218972
I'll have to post a techinfo procedure for the complete installation of a newer stereo into the 92-93 models. I will take some pictures soon.
This should close this thread out, finally.
#20
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Lets see.
Stereo from 2001 Trans Am - $165
New Climate Control Head - $125
Misc. Wiring Harnesses - $5
1994 Serice Manual / Wiring Diagram - $20
Old Radio in trunk (not used anymore) - $10
I don't even want to add it up, because I could have found a 92-93 CD player for around $225.
Stereo from 2001 Trans Am - $165
New Climate Control Head - $125
Misc. Wiring Harnesses - $5
1994 Serice Manual / Wiring Diagram - $20
Old Radio in trunk (not used anymore) - $10
I don't even want to add it up, because I could have found a 92-93 CD player for around $225.