When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
The backup light switch is on the driver side of the transmission case. The connector for the backup light harness is near the master cylinder on the cowl. Disconnect the harness and see if it still blows the fuse. If not, then the problem is in the wires going to the switch. Check them from cowl to switch for places they might be getting a ground and shorting. Could be the switch shorting as well. If all checks out okay the problem could be in the harness going to the rear of the car or the lights themselves but I'd bet on the wires to the switch.
Last edited by dkleather; Sep 7, 2016 at 09:15 PM.
^^^this. Dead short somewhere in the circuit. If the circuit is shared, check the shared loads. Had an issue years ago with the wipers on my '67 GTO, turned out to be a penny that had fallen into the shifter gate and was shorting the reverse light switch. Every time I backed up, the wiper fuse would blow and the wipers would stop working. That was a fun one!
The pink wire on the b/u switch connector also feeds the park brake warning lamp and the gauges. Does the fuse blow when the car is not in reverse, or only when put in reverse? The easiest place to get a short is in the pink wire by the switch in the transmission. It's close to exhaust if under car, and can break off and short to the transmission, or the switch case itself. As said, if you disconnect that two wire connector by the master cylinder (one pink one green) and it still blows, it's not a switch problem.
The backup light switch is on the driver side of the transmission case. The connector for the backup light harness is near the master cylinder on the cowl. Disconnect the harness and see if it still blows the fuse. If not, then the problem is in the wires going to the switch. Check them from cowl to switch for places they might be getting a ground and shorting. Could be the switch shorting as well. If all checks out okay the problem could be in the harness going to the rear of the car or the lights themselves but I'd bet on the wires to the switch.
thanks for the info will look into it over the weekend
Hi Guys,
Had some medical issues come up and just got back to car yesterday. Disconnect plug by master cylinder put in new fuse went for a ride fuse was still good went out again last night checked fuse today and it was blown.So from every ones feed back that eliminates the switch so how to i proceed to check from the firewall back?
If the fuse blows with the pink and green wire connector disconnected, the problem is not from the firewall back. It's in the pink wire circuit that feeds the gauges, park brake light, etc. Either you have too small a fuse in or you have an intermittent short. Take a look at the diagram and follow the top fuse pink circuit for all it feeds.
