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I have a 72 convertible. The previous owner installed a toggle below the dash and ran a wire to accessory on the fuse panel. See pic. (By the way, what is the round light yellow thing at the top of the panel? It says "SAE 3 lamp" on it. I don't see this in any wiring diagrams)
Anyhow, using the toggle, the top worked fine for the 4 months I've had the car until this week. It doesn't seem to be getting any power. Thought I'd ask you guys about the breaker in firewall. I don't see one. Do you know if the 72 is supposed to have one? I may be blind. Any other suggestions to try and troubleshoot?
Suddenly this week, I have no power to the convertible top switch. Before I embark on an epic journey of tracing potential issues, I thought I'd ask the masses where they'd start.
First things first, check your 30amp breaker located on the firewall behind the brake booster. You should have 12V+ on both terminals if working correctly.
First things first, check your 30amp breaker located on the firewall behind the brake booster. You should have 12V+ on both terminals if working correctly.
The yellow round thingy is the hazard flasher. The top does not work through the acc pwr relay as I had previously thought. Check the fuse on the fuse panel for pwr.
(By the way, what is the round light yellow thing at the top of the panel? It says "SAE 3 lamp" on it. I don't see this in any wiring diagrams)
Thanks guys
You would find the round light yellow thing (located/contained within the fuse block) located in the 1972 CSM in the Chassis Electrical section identified in the A-Body Fuse Block figure as the HAZARD WARNING FLASHER.
I moved your post from an old thread you resurrected to the thread you started about your problem it is in post #1. Since your wiring has been modified with the toggle sw. there is no way for us to know what you have there. My advice is to trace the wiring and see where you lost power and go from there.
The convertible top, power windows, power seats, etc are all shown in the Fisher Body Manual, not the CSM. Also, these high current circuits not only use a circuit breaker, but they also use an isolation relay that is under the driver side kick panel. The relay DOES go bad after half a century.
This is a diagram of the Front Harness Circuit for the 1971 Oldsmobilte "A-67" Styles from the Fisher Body Service Manual (NOTE: It is not from a 1972; although, I have a suspicion 1972 is probably same as 1971). A-67 implies reference to A-Body convertible and includes 162 (Power Top Up Cycle) & 163 (Power Top Down Cycle) if that helps.
While you haven't stated otherwise, I assume you have no voltage - so this diagram may assist. I am suspecting you cannot hear any ram activity w/in the hydraulic power top cylinders. I'm very suspicious of the toggle switch itself. The Power Top electrical circuit was not designed to operate via a two-position "ON" or "OFF" toggle switch. There could "possibly" remain the notion the Power Top motor has gone bad if someone inadvertently left the toggle switch in the "ON" position - feeding continuous voltage to the Power Top motor (albeit - it would never shut off and possibly burn out). Although, Joe's suggestion of the driver's side kick panel relay may be the issue. Personally, I'd remove/replace (whatever you need to do) the toggle switch from the complete circuitry - that just isn't going to cut it. Get a "proper" functioning Power Top Switch after you've isolated the electrical issue.
Last edited by Vintage Chief; Oct 11, 2019 at 05:45 PM.
Reason: sp
OK. So, I thought about this longer than five minutes. Are you sure what you're referring to as a TOGGLE SWITCH is truly a TOGGLE SWITCH. AFAIK, there are basically x4 styles of toggle switches - SPST, SPDT, DPST & DPDT; yet, each of these type toggle switches would not turn off or disengage the voltage to the power top hydraulic motor. If it was one of these types toggle switches, the toggle switch would only allow a continuous feed of voltage to the UP side or the DOWN side of the switch to motor. You'd never be able to turn the voltage OFF and disengage the power top motor. Post a picture of what you're referring to as a toggle switch. It would have to have a minimum of three positions or be some type of rocker switch.
OK. So, I thought about this longer than five minutes. Are you sure what you're referring to as a TOGGLE SWITCH is truly a TOGGLE SWITCH. AFAIK, there are basically x4 styles of toggle switches - SPST, SPDT, DPST & DPDT; yet, each of these type toggle switches would not turn off or disengage the voltage to the power top hydraulic motor. If it was one of these types toggle switches, the toggle switch would only allow a continuous feed of voltage to the UP side or the DOWN side of the switch to motor. You'd never be able to turn the voltage OFF and disengage the power top motor. Post a picture of what you're referring to as a toggle switch. It would have to have a minimum of three positions or be some type of rocker switch.
You are forgetting about toggle switches with a center-OFF position. THAT is what the 'vert top switch is, and it has a spring loaded return to center when released feature (UP/DN positions are momentary). Sometimes a "toggle switch" uses a rocker instead of a long lever to actuate the electrical contacts (like the factory top switch), but the electrical action is the same.
Last edited by JohnnyBs68S; Oct 11, 2019 at 05:48 PM.
You are forgetting about toggle switches with a center-OFF position. THAT is what the 'vert top switch is, and it has a spring loaded return to center when released feature (UP/DN positions are momentary). Sometimes a "toggle switch" uses a rocker instead of a long lever (like the factory top switch), but the electrical action is the same.
Indeed, I understand. But, without a clearly defined "type" of toggle switch or an image of this suspected toggle switch, it's a crap shoot right now. And, indeed I did suggest a type of 'rocker' switch but that's exactly what was in the vehicle to begin with so why replace a rocker switch with what the OP identified as a toggle switch.
In any case, it should be an easy enough diagnosis at the suspected toggle switch to simply remove it or test if there is voltage going into and out of the wires leading into and out of the toggle switch itself as a starting point.
No breaker on the firewall. Might be different in 72, i have a 68. The rectangular thing is your high speed hvac fan relay. I do see two fat wires going through the firewall. You might see where these go. One could lead to your toggle switch and I’d guess the other is for an aftermarket fire starter, sometimes called an amp gauge. If one goes to your toggle switch, the switch might be burned out. If this is the case, you’ll at least want to put a 30 amp fuse inline or better yet, restore the factory circuit.
