Peter Wilson Posted August 27, 2024 Posted August 27, 2024 Hi Jonny, I have just installed a front fuse panel in a 1980 930. Everything is working OK except the headlights. I have removed the prior J West relay kit and checked all connections. The relays are clicking, so I am confident of earthing. The lights aren't behaving properly in terms of ignition on/off and light switch position so I suspect a switch logic problem between the original wiring and new panel. I have found the attached schematic on a previous discussion topic and will be able to debug with a bit more info. Can you please confirm the following terminal numbers: T43 = H T15 = 1 T13 = 2 T11 = 3 T9 = 4 Can you please advise the fuse board terminal numbers for T10, T12, T14 and T16? Also, where is T33, which supplies +12V when T43 (H) is not used? Many thanks, Peter. Quote
Peter Wilson Posted August 31, 2024 Author Posted August 31, 2024 Hi Jonny, I have done some debugging based on the circuit diagram. I also found the smaller terminal numbers on the PCB which answered my previous questions. Here is the situation: 1) I have 12V at T33 (and T43). The fuse panel is well earthed. 2) Relay 1 clicks when I apply +12V to either T15/T13 3) Relay 2 clicks when I apply +12V to T11 4) As expected, low beams come on when I apply +12V to T9 (relay bypass) 5) Applying +12V directly to T16 makes left main beam come on (same for T14, T12 and T10 and their respective lamps) BUT, despite relays clicking and having power at T33, no headlights illuminate. It is like there is no power connection to the input or output of the relays. Can you please provide a likely explanation and fix? Many thanks, Peter. Quote
Jonny Retrofit Posted September 6, 2024 Posted September 6, 2024 There are several thousand of these panels in service and we have not changed the design recently. On the face of it, it sounds like a bad PCB track or a fault with the relay. Since you have issues with both main and dip, the chances of BOTH relays being bad are so small so this can be discounted. Perhaps the voltage feed to T33 from the car is not sufficient? Try wiring the + of the battery direct to the H terminal (43). If the lights work, then the problem lies in the power feed. It is often the case that a DVM (meter) will show you 12V, but there is not sufficient current to power something like a headlamp. Quote
Peter Wilson Posted September 11, 2024 Author Posted September 11, 2024 Hi Jonny, I had previously tried wiring T43 to the battery 12V and I tried it again just now based on your suggestion. Still no high or low beam. I agree that a bad track or dry joint to terminal 2 of the relays might be the problem, and that both relays being bad is unlikely (especially as they are both clicking). I also thought that maybe the relays were mounted upside down. However, looking at photos of other fuse panels, the relays are always mounted "upside down" plus it looks like the pin arrangement of the CB1-P-12V ACB13101 wouldn't permit this assembly error. Any suggestions for next steps? Regards, Peter. Quote
Jonny Retrofit Posted September 16, 2024 Posted September 16, 2024 Relays cannot be fitted incorrectly - pins only go in one way. When you pull the headlamp fuses, do the LEDs light up when the headlamps are switched on? Quote
Peter Wilson Posted September 17, 2024 Author Posted September 17, 2024 Hi Jonny, none of the LEDs illuminate when switching on lights and pulling fuses. However, if I apply +12V to T9 (relay bypass), the low beams come on, and LEDs D5 and D6 illuminate when FU5 and FU6 are pulled. I can confirm that I have power from light and dip switches to terminals T15, T13 and T11 when correct switches are operated. Regards, Peter. Quote
Jonny Retrofit Posted September 18, 2024 Posted September 18, 2024 if it were me, I would take a small automotive bulb to test. Do not use an LED - needs to pull some current so use a 5W side lamp or something. It really is a simple circuit. Connect one side of the bulb to chassis/negative. Use the bulb to confirm: 1. 12V at T43 (H Terminal) 2. 12V at T15/13 when main beam is operated. Relays should also click. Now connect the bulb to T16 and operate the main beam switch. Bulb should light up. Post the results here. The most likely cause I would say is something to do with the 'unwire' of the previous relay kit. If the small bulb does not work, I would be visually inspecting the back of the fuse panel in the area of the relays. Take a hi-res photo and post it here. You may as well post a picture of the front wiring side too. I am assuming all along that when you are doing these tests, you still have the ground connected. It can be misleading if you are testing with the fuse panel not screwed to the metal frame. Quote
Peter Wilson Posted September 19, 2024 Author Posted September 19, 2024 Hi Jonny, I performed the tests with a test lamp, with the same results as before and as expected (power at T43, T15/T13, but no power at T16). I didn't suspect a problem with the old relay "unwire" as I had tested that all lights worked fine when reverted to the original wiring. So I disconnected the top connections of the fuse panel to allow inspection and probing of the rear. The problem was immediately visible - whilst both relays had the primary terminals soldered, only the input (T30) of the secondaries were soldered, with both NO and NC terminals not connected. See picture attached. This defect perfectly matches the symptoms of clicking relays but no secondary current. I soldered the joints and reassembled the panel and the headlights now work as they should. One note here - the fog lights made the high beam illuminate. This is because of a relay logic interlock incorporated by Porsche, such that the fog light relay primary is earthed via the high beam circuit (your T13). With the standard fuse board, activating the fog light relay with the high beam on gives no voltage difference across the primary and the fog lights are turned off. However, with your board, the current from the fog light primary then flows through the RL1 primary to earth, activating it and turning on the high beam. I fixed this by connecting the fog light relay earth to T14 (high beam relay output) instead of T13, and the interlock now works as it should, I would suggest adding this fix to your installation instructions, as well as improving visual or functional testing to avoid defective boards slipping through. Regards, Peter. Quote
Jonny Retrofit Posted September 19, 2024 Posted September 19, 2024 Wow, that is a first. According to our records, you ordered this back in June 2021 so it quite possibly a batch from the bad days of the pandemic. Lots of companies were short staffed and under enormous pressure to deliver so quality did suffer. Nonetheless, apologies and I have raised this with our factory as the QC inspection has clearly not been carried out. I am further baffled as the panels are 'flow soldered' - meaning a wave of solder goes across the entire board. My guess is that during the pandemic some of the panels were hand soldered. That's interesting regarding the fog light - surely this would have occurred with your previous relay kit also? Quote
Peter Wilson Posted September 20, 2024 Author Posted September 20, 2024 Yes, I ordered the board some time ago (as a package deal with a CDI+ unit) and have only got around to fitting it now. It looks like the rest of the board was flow soldered - perhaps the relays were not available and were hand soldered later? The problem with the fog lights turning on the high beam did not arise with the previous relay kit, as only the high-beam feed from the dip switch was redirected to the relay. The earth wire from the fog light relay remained connected to the fuse and this was equivalent to splitting T13 from T15 on your board. Hence the fog light relay couldn't earth through the high beam relay. Anyway, glad to have it all sorted! Quote
Garry Wiseman Posted October 28, 2024 Posted October 28, 2024 So I am going through a similar journey where I can’t seem to get the headlights to work correctly despite the board being grounded. My board was from all the way back in March 2019, version 1.3. Not sure if I have the same issue with the board described above, but here’s a sexy snap of what’s behind the relay area. Does this look correct? Quote
Jonny Retrofit Posted December 11, 2024 Posted December 11, 2024 That looks ok to me. Here's how to test: Quote
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