71-72 B Body Rallye Cluster electrical Questions

[jonnymopar]

Got some 71-72 B Body Rallye Dash questions. My car was originally equiped with the standard dash so I don't have an original rallye harness to look at. I bought the new harness form YearOne. 1) Does the Blue wire W/ white stripe (A) plug into the 12 V supply to the Voltage drop (B)? This wire seems to be tied into the ignition switch (power to it when key is on) so it makes sense this is where it goes although it doesn't seem to reach.

Does a ground have to be plugged into (C)? There's 2 black wires form the harness but they're not wide enough to plug onto this post.

Theres a green wire (D) and another Blue wire w/ white stripe (E) which alos seems to be tied to the ignition switch, any ideas where these are supposed to go?

Any Help is greatly appreciated.

Jonny

 

[furious70]

Mymopar.com I think has all the wiring diagrams. I've gone through the same exercise working on converting mine.

 

[72RoadrunnerGTX]

Got some 71-72 B Body Rallye Dash questions. My car was originally equiped with the standard dash so I don't have an original rallye harness to look at. I bought the new harness form YearOne. 1) Does the Blue wire W/ white stripe (A) plug into the 12 V supply to the Voltage drop (B)? This wire seems to be tied into the ignition switch (power to it when key is on) so it makes sense this is where it goes although it doesn't seem to reach.

Does a ground have to be plugged into (C)? There's 2 black wires form the harness but they're not wide enough to plug onto this post.

Theres a green wire (D) and another Blue wire w/ white stripe (E) which alos seems to be tied to the ignition switch, any ideas where these are supposed to go?

Any Help is greatly appreciated.

Jonny

Of the two 18ga black wires, one is the cluster ground (C), and one is the keyed power supply to the voltage limiter (B). The original Rallye harness uses a wider female Packard terminal on the ground lead. The other end of that lead is the harness ground near the far driver’s side dash frame with stared ring terminal, if the replacement harness has two of the same size, verify by checking continuity to the harness ground ring terminal.

The single Packard blue with white tracer (A) is ignition 1, for optional power windows harness, not used otherwise.

The two ring terminals (D&E) are for the concealed headlights relay/breaker, again disregard if not equipped, be sure to insulate both ring terminals if not used.

BTW, assuming that ammeter is intentionally mis-wired.

 

[jonnymopar]

Mymopar.com I think has all the wiring diagrams. I've gone through the same exercise working on converting mine.

I'll check it out but I should have mentioned I did look at the schematic and at least the one I have doesn't show any of these wires. Which you would think the power supply wire to the Voltage drop is pretty important.

Thanks Furious

 

[jonnymopar]

Of the two 18ga black wires, one is the cluster ground (C), and one is the keyed power supply to the voltage limiter (B). The original Rallye harness uses a wider female Packard terminal on the ground lead. The other end of that lead is the harness ground near the far driver’s side dash frame with stared ring terminal, if the replacement harness has two of the same size, verify by checking continuity to the harness ground ring terminal.

The single Packard blue with white tracer (A) is ignition 1, for optional power windows harness, not used otherwise.

The two ring terminals (D&E) are for the concealed headlights relay/breaker, again disregard if not equipped, be sure to insulate both ring terminals if not used.

BTW, assuming that ammeter is intentionally mis-wired.

Ah, I see. I was thinking backwards in the electricity flow. I thought positive was supplying 12V to the voltage drop then 5V to the gauges. But the positive is actually the colored ends of the gauges and ground is tied together back to the voltage drop. Now it makes sense why all those wires are tied together in black leading to the Voltage drop. And yes, one of the black wires has continuity to the ring terminal thats grounded to the dash frame, driver side.

So just to clarify the ground wire tied to the dash frame ring terminal (driver side dash frame) goes to the (C), which is too narrow in the aftermarket harness. I'll have to see if I can get a new connector.

The other goes to (B). I don't have the column / ignition switch attached so that's why I wasn't getting continuity to ground on this wire.

Don't have electric window so I'll leave the Blue Packard connector disconnected. BTW, I didn't know thats what they were called.

And don't have concealed lights, So I'll insulate them off. This explains why these wires weren't in the Standard dash harness I do have.

Yes, I intentionally tied the Amp meter leads together to avoid any overheating or fire.

72RoadrunnerGTX, that was a huge help. Thank you very much for the info.

BTW, My buddy has a Vitamin C Orange 72 Road Runner GTX. A very cool car. I sold the same friend my 72 Satellite slant 6 Winchester Gray.

To anyone else who finds this thread in the future I have a video on this topic. A 2nd (Jonny Mopar) video will being going up soon with the finishing touches described above in case you're looking for answers on the same harness.

 

[72RoadrunnerGTX]

Ah, I see. I was thinking backwards in the electricity flow. I thought positive was supplying 12V to the voltage drop then 5V to the gauges. But the positive is actually the colored ends of the gauges and ground is tied together back to the voltage drop. Now it makes sense why all those wires are tied together in black leading to the Voltage drop. And yes, one of the black wires has continuity to the ring terminal thats grounded to the dash frame, driver side.

Keyed 12v positive is being supplied to the input side voltage limiter (voltage drop?) at your B labeled terminal via the accessory circuit, will show continuity to the 12ga black wire at the ignition switch Molex connector if testing. On the output side of the voltage limiter is averaged to about 5 volts, split out to the three sweep gauges through the small four connector splitter pigtail from the voltage limiter. The colored connections at the gauge are variable grounds as determined by the various senders.

So just to clarify the ground wire tied to the dash frame ring terminal (driver side dash frame) goes to the (C), which is too narrow in the aftermarket harness. I'll have to see if I can get a new connector.

The two different sized Packards are designed to prevent the smaller key power Packard from fitting onto the wider grounded spade on the voltage limiter mounting bracket. If the replacement harness uses Packards of the same width, unlike the factory harness, you could trim down the voltage limiter ground spade should it prove difficult to locate the 3/8” wide Packard terminal being careful not mix them up.

Yes, I intentionally tied the Amp meter leads together to avoid any overheating or fire.

No comment.



Note the error in this factory Rallye cluster wiring diagram relating to the voltage limiter pig tail, no continuation to the fuel gauge indicated.