# 2003 Toyota Corolla Electrical issue **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** electrical-wiring\ **Created:** [November 15, 2015, 6:40am UTC](https://community.cartalk.com/t/2003-toyota-corolla-electrical-issue/91705 "2015-11-15T06:40:11Z")\ **Posts on this page:** 2\ **Page:** 2
**Author:** ![circuitsmith](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/circuitsmith/32/40376_2.png) [@circuitsmith](https://community.cartalk.com/u/circuitsmith)\ **Post date:** [November 18, 2015, 7:43pm UTC](https://community.cartalk.com/t/2003-toyota-corolla-electrical-issue/91705/21 "2015-11-18T19:43:30Z")
There’s a problem with the wiring (harness) from the computer to the coils, or you have multiple bad coils. Try swapping coil 4 with one of the others and see if the igniter fault moves to #4. It’s possible some kind of electrical surge damaged the coils & alternator. > **[P1300 Toyota - Igniter Circuit Malfunction No. 1](https://www.engine-codes.com/p1300_toyota.html)** > > Direct Ignition System (DIS) is a 1-cylinder ignition system that ignites one cylinder with one ignition coil. Ignitor is integral to ignition coil. The Engine Control Module (ECM) determines ignition timing and outputs a ignition signal (IGT) for... ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [November 19, 2015, 9:52am UTC](https://community.cartalk.com/t/2003-toyota-corolla-electrical-issue/91705/22 "2015-11-19T09:52:56Z")
Circuitsmith is correct, you may have a problematic wiring harness. One idea before starting down that path: Does this car seem to run ok now, and all the problems you reported above – relay clicking, etc – have been eliminated after the alternator change-out? If so, it is possible the computer is just reporting codes now it had already stored before. [Previous page](https://community.cartalk.com/t/2003-toyota-corolla-electrical-issue/91705.md?page=1)