Here's a breakdown of how to approach this:
1. Identification and Location:
* Find the flasher: This is crucial. 1967 Cadillacs likely have the flasher unit under the dash, possibly near the fuse box or other electrical components. Consult your owner's manual (if you have one) or a wiring diagram for the exact location. Sometimes they're in the trunk.
* Type of flasher: Determine if it's a thermal (bimetallic) flasher or an electronic flasher. Older cars usually used thermal flashers. Knowing the type helps determine the appropriate troubleshooting and repair steps. You might need to remove it to see its markings.
2. Troubleshooting:
* Visual Inspection: Check the flasher for any obvious signs of damage, such as burnt components, loose connections, or physical damage to the casing.
* Testing Continuity: With the flasher removed, use a multimeter to check for continuity across its terminals. The continuity should vary depending on the type of flasher and its state. This requires some understanding of how the flasher works electrically. Refer to a schematic or online resources specific to your flasher's model number if possible.
* Testing in Circuit: If the flasher seems faulty, you might be able to test it *in-circuit* using a test light. This is more challenging, and requires carefully disconnecting and connecting wires to avoid shorts. Use caution. A wiring diagram is essential here.
* Check Bulbs and Wiring: A faulty turn signal bulb or corroded wiring can also cause flasher problems. Test the bulbs and inspect all related wiring for breaks, corrosion, or loose connections.
3. Repair or Replacement:
* Thermal Flasher Repair (unlikely to be successful): Thermal flashers are rarely repairable. Internal components are typically sealed. Any attempt at opening and repairing it could likely cause further damage.
* Electronic Flasher Repair (possible, but specialized): Electronic flashers are more complex and may be repairable by someone with electronics experience. If a component fails, replacing it might be feasible, but finding the right replacement might be challenging.
* Replacement: The most practical approach is usually replacing the flasher unit. Find a replacement flasher that matches the original's specifications (socket type, voltage, and load). Auto parts stores (online or brick-and-mortar) should have suitable replacements. Make sure to get the correct amperage and voltage rating.
Important Considerations:
* Safety: Disconnect the battery's negative terminal before working on any electrical components to prevent electrical shock.
* Wiring Diagram: A wiring diagram specific to your 1967 Cadillac Fleetwood limo is invaluable for troubleshooting and repair. These can sometimes be found online or through Cadillac restoration clubs.
* Professional Help: If you're not comfortable working with car electrical systems, consider taking your car to a qualified mechanic or auto electrician. Incorrect repairs can cause further damage.
In short, while the flasher unit itself is relatively simple, diagnosing the *cause* of the problem requires methodical testing and a good understanding of automotive electrical systems. Replacement is often the easiest and safest solution.
