C2 Ignition Switch wiring, ground missing?

[Alan Drake]

Putting my instrument cluster back after being out for 30 years, was using a home made real wood dash.
The problem I'm having is that the ignition switch connector only has four connection on it. A connection to the GND terminal is missing.
Need the answer to Question 2 in detail. Rest of comments you can skip, just added for general info. Thanks All!

Question 1. Does switch get its ground from the case of the switch?
Question 2. Should there be a small connection at the grond terminal about 3"

long and terminating with a female connector that plugs into the

radio cap, 1960960? If so what Color and Lenght should wire be and

what color is connector.

Finding;
The 63/64/65 Shop Manuals show cap, 1960960, connecting to "Ignition Connector" and appear to be going to the ignition switch as one would expect. It is this wire I believe is missing from my connector.

The 64 AIM, page D351, shows cap, 1960960, going to "Prod Radio Capacitor (brown wire)" I do have that brown wire, however it is now connected to a cap, 1960960, which is attached to the frame with the radio ground connector 14 black wire also attached there.

It appears to me that the AIM is in error relative to the connection of the ignition area cap, 1960960.

Some more info;

ON THE PLUS side, the AIM, page D351, shows a third cap that the 63/64/65 Shop Manuals do not show. This cap is number 3844184 and is on my unit.
Third Cap; The markings are in ink along the side as opposed to the end. it is marked as "Sprague 5(?) MFD 3844184" . It has a 3" long blue pigtail that terminates at a black block (1/2 X 1/2 X 1/4 inches) with a nail on the side. The cap is terminated on the 20 tan wire of the brake warning switch.

[Joe C.]

Re: C2 Ignition Switch wiring, ground missing?

Alan:

One quick response relating to the next-to-last sentence of your post. All of the RF noise suppression capacitors are rated @ .5 microfarads (MFD).

Joe

[Joe C.]

Re: C2 Ignition Switch wiring, ground missing?

Alan:

The following assumes that 1964 (yours) and 1965 (mine) share wiring config in this area.

1. According to the schematic, the ignition switch has no ground connection. This makes sense, because it does not need one. It merely completes the circuit of the "hot" leg....between "bat" and either "sol(enoid)", "ignition" or "acc(essory)". There is a ground lug at the top of the cluster housing, and this ground is necessary for proper operation of the fuel gauge, and cluster lighting.

2. There is a RF niose capacitor which is mounted just below the ignition switch. It does, indeed, connect to the brown wire vis a small pin. This brown wire is for the emergency brake warning lamp. Therefore, it has no connection to the ignition switch.

Joe

[Alan Drake]

Re: C2 Ignition Switch wiring, ground missing?

Thanks for info Joe.
OK, I understand the ignition switch operation with no ground needed, however is there a wire that exits your connector?

If you look at your 65 Shop Manual, page 13-3, you can see the cap connected to the "Ignition Connector" I believe the AIM for 64 to be wrong since the brown wire (16BRN)shown on the wiring diagram, page 12-6, plugs into the cap mounted on the frame (for 1964) which is also used (frame) as the radio connector ground (from plug).

Believe this configuration to be correct since I've owned the car since 67 and known that no radio problems occured before that which would warrant the adding of a cap.

Do you have the third cap I spoke of (3844184, the .5MFD)?
Do you have the cap (1960960)mounted on the frame member where the radio ground connector goes to?
If you have neither of these I would guess that a radio problem in 63/64 was being attempted to be fixed with the final fix being the removal of the 2 other caps I have. The final fix being the use of the one cap below the ignition switch to filter the parking brake light.

[Joe C.]

Re: C2 Ignition Switch wiring, ground missing?

Alan,

As shown on the 1965 wiring schematic, there is no indication of a wire that exits separately from the ignition switch connector. The connector is a clear polyethylene molded assembly that surrounds the interfacing lugs and hold them to the switch housing with three lugs with snaphooks on the ends.

There are two capacitors mounted to the cluster housing for 1965 (and, probably 1964). The other capacitors are for the brake light switch, directional flasher can, blower motor, voltage regulator, and ignition coil.

Joe

[Alan Drake]

Re: 1964 Instrument Cluster has 3 caps

Yes the 63/64/65 Shop Manuals show only 2 caps on Instrument Cluster while the 64 AIM shows another cap (third one) above the Tach connected to tan brake warning light. Do not know if 65 still had this extra cap. Note, cap is not the standard GM part, but a Sprague cap marked in ink along its side. Have seen this discussed in past postings.

As for the connection at the Ignition Ground, the 63/64/65 Shop Manuals reference that the cap, 1960960, gets connected to the "Ignition Connector" and does appear to go in that direction.

The electrical diagrams do not reference any connections to cap's so I'm not surprised that a wire connection is not shown at the ignition switch.

Also note; the 65 ignition switch is different for 63/64. The 63/64 connector is also black.

Thanks for the info, however I'm still not sure of something.

[John H.]

Re: 1964 Instrument Cluster has 3 caps

The capacitor attached adjacent to the ignition switch gets connected to the 16-ga. ('63-'66), 12-ga. ('67) brown "radio capacitor" wire from the instrument panel harness.

[Alan Drake]

Re: 1964 Instrument Cluster cap locations

Well;
Finally found out why I appeared to have an extra cap associated with my instrument cluster - I DON'T

The cap mounted by the ignition switch on many 64's is NOT on mine. The cap on the frame (instrument support member) near the radio is where the brown wire goes as it has since I've owned the car. Sometime during the 64 year (March on) the cap was moved to the normal ignition switch location.

I also notice that my ignition switch connector is the old 63 two prong style connector - not the newer three prong one. also foung that the turn signal flasher is the 63 model, Stat 143. Guess GM used all its old parts when possible.

Thanks for joining in the discussion, its fun to be a member
Alan