89 S4

I was replacing a blown brake light fuse and I noticed relays I and XIII were empty. According to my chart, I isn't used and XIII is for foglights. Is there anything else tagged onto that relay? I ask because I have a few electrical issues to track down, but knowing what else uses that relay will make life easier.

Also, is that a typical "53" relay?

Thanks.

From Roger's site

An actual picture of an 89 (a friend's car). A 5-speed so the Kickdown Relay is absent

I have the same chart. Thanks for the pic.

But mystery solved... I too have a 5 spd. I saw the open slot and thought it was 13 but instead it's XV and empty b/c I don't need the kickdown relay.

So why is the Reverse Light section (22) 'hotwired'? Mine was too and I put a relay in there. Do I need to find the hotwire and replace it?

I remover one time accidentally putting a relay in the reverse light socket on a manual and the car would not start. Threw some silicone caulking in that socket so there’s no mistake again.

IIRC it's the neutral safety bypass. As stated above. The car wont start with a relay in that socket because there is no signal coming from a non existent neutral switch.

Almost - it is related to that. Auto cars have feedback from the trans selector switch to say you are in reverse - which is a low current switch so it needs a relay to drive the reversing lamps (~42W). Manual cars have a high current switch in the gearbox for reverse so can drive the reversing lights directly - the "Relay Bridge" [M:928.615.125.00] as listed on the diagram is what you need (not a 'hot wire'), this allows the manual trans switch to directly drive the lights. So only auto's need the relay - that's the part # note on the diagram in the relay box: [A: Auto, M: Manual]

Auto's also do have a neutral (safety) switch from the same trans selector to disable the starter relay when not in park/neutral, manual cars don't - so this always enabled on a manual by grounding that wire near the trans (the relay is always there for the starter in both - for all but the earliest cars). The reverse light relay or bridge (or neither) don't have any affect on starting.

Note that this function is Relay position XIII only on some years - better to retitle the thread Reverse Light / Backup Light Relay so others will find it based on the function and not be confused.

Alan