EvergreenZ71

Long time viewer, first post here (I'm usually on the Tahoe/Yukon forum and formerly on Z71Tahoe-Suburban) Resurrecting an old thread for my first official post as I'm trying to add RAP (or accessory) circuits to both my 2009 Tahoe and 2010 Suburban. First and foremost; member Diesail, thank you for the great write-up! I hope no one minds that I'm going to copy & post (with due credit) this information to the Tahoe/Yukon Forum as I spend more time there and this information hasn't been transferred there yet. Here is some additional pertinent information as of July 2023: Member Oldergeek posted that the relay pigtail (and possibly the relay itself?) he purchased was not wired the same as the OP (maybe the same issue as ZDale59 - see below?) and shared a website with updated relay schematics and pin codes, but unfortunately that site is also no longer functioning. OP directions: Relay Post to Connector Pin list with identified pigtail colors: Relay Pin 30 – constant 12v source [Blue wire] – X14 connector Pin 2 or Pin 5 [Battery feed] Pin 2 has 15 amps Pin 5 has 30 amps Relay Pin 85 – Relay trigger positive [White wire] – X14 connector Pin 8 [RAP feed] Relay Pin 86 – Relay ground [Black wire] – X14 connector Pin 1 [Ground] Relay Pin 87 – NO (normally open) circuit / aka switched circuit [Yellow wire] – Out to accessory or auxiliary fuse block for further distribution Relay Pin 87a – Not used: remove or seal wire / connection [Red wire] – NOT USED (this pin creates a normally closed / ON circuit) DIODE: connects Relay pin 85 & Relay Pin 86 with white Oldergeek directions: Relay Post to Connector Pin list Relay Pin 30 – constant 12v source [Blue wire] – X14 connector Pin 2 or Pin 5 [Battery feed] Pin 2 has 15 amps Pin 5 has 30 amps Relay Pin 85 – Relay ground [Black wire] – X14 connector Pin 1 [Ground] Relay Pin 86 – Relay trigger positive [White wire] – X14 connector Pin 8 [RAP feed] Relay Pin 87 – switched circuit [Yellow wire] – Out to accessory or auxiliary fuse block for further distribution Relay Pin 87a – Not used: remove or seal wire / connection [Red wire] – NOT USED DIODE: connects Relay pin 85 & Relay Pin 86 with white EDIT: After additional research both are basically correct. According to further information about relays from 12voltplanet (https://www.12voltplanet.co.uk/relay-guide.html) ... the coil should be fed with +12V to terminal 86 and grounded via terminal 85, however in practice it makes no difference which way around they are wired, unless you are using a relay with an integrated diode. Thus the difference or specificity is directly necessary and integrated with the inclusion of the recommended diode. Most importantly, to retain alignment with the GMUpfitters directions, read the relay schematics for the relay & relay pigtail you purchase and make sure of the following: The ground indicated for YOUR relay is connected to X14 connector Pin 1 Note, some relays reference the switch on the negative side The positive trigger indicated for YOUR relay is connected to X14 connector Pin 8 The recommended diode connects with the cathode (stripe) towards the positive trigger (X14 connector Pin 8 ) and the anode (other end) towards the ground (X14 connector Pin 1) Relay Specifics: You must use a "normally open" relay to make use of RAP or accessory power An open relay is not connected / off A closed relay is connected / on I believe both 4-pin (Normally Open) or 5-pin relays (using Pin 87) can be used Do not use 4-pin (Normally Closed) relays nor 5-pin (using Pin 87a) In regards to the diode referenced by member xPosTech (Tech Bulletin 86) and reinforced by member Cujo8. Note: member Bill in Niantic had used the setup without a diode for 2(+) years without problem, but it sounds like adding a diode may be a safer plan. GM Upfitter identifies diode 12112422 specifically Install a diode, P/N 12112422, across the coil of the solenoid. It is important that the striped end of the diode be connected to the positive terminal of the coil and the other end of the diode be connected to ground This appears to be identified as a 300 volt, 3 amp diode (though I also see where it is identified as a 400 volt, 3 amp diode) xPosTech identifies another diode (1N4003) that appears to be much more readily available and appears to be a 200 volt, 1 amp diode. Diode 1N5404 appears to be the same as GM 12112422 and may be the part number for what Cujo8 identified: {Cujo8} added a 3amp, 400PIV diode to the harness between white(85) and black(86) pigtail wires just behind the black socket to give the diode protection to this relay assembly (Diode stripe-end connector should be attach to the white #85. connector) The diode (and complete connection) was drawn out by member ZDale59 (though it was posted as a question that was not replied to): The diagram above is good ... but member Oldergeek identified a problem detailed above . Different relays may be set up in reverse! The cathode (the line at the point of the arrow representing the end with the stripe) attaches towards the trigger (aka the ignition / + RAP source) The anode (other end of the diode) attaches towards the ground I also believe the OP only had the relay connecting to connector Pin 8, but I do not see this creating a problem whether the accessory ground is attached or not (i.e. directly grounded to the frame) since they are both grounds GM Connector 20791502 (optional in directions) is discontinued and the option from member CGalford is no longer functioning. There is an aftermarket replacement option that appears to be already wired for both the 15 & 30 amp output: https://www.ebay.com/itm/222369004159 Purchasing this appears to prevent the need to get the Female GT 280 terminals The primary difference I see between the 2009 & 2013 GM Upfitters Electrical manuals as it pertains to this project is that the 2013 includes the information contained in Tech Bulletin 86 (covering the Installation of a Diode to Suppress Voltage Spikes identified by member xPosTech) which is evidently not readily available from GM anymore: https://www.gmupfitter.com/wp-content/uploads/2021/05/2009_LD_ElectricalPickupsChassisCabs_100813.pdf https://www.gmupfitter.com/wp-content/uploads/2021/07/2013_LD_ElectricalPickupsChassisCabs_100713.pdf (see page A-14) The dual relay posted by member TopDJ is no longer functioning as the website / store seems to be gone (http://www.aqua-man.com/row_num.asp?ic=80056&froogle=1). I found a few that sound similar, but not sure they are DC nor their voltage, but see my question section below for some possible similar alternatives. Additional confirmation pulled from: https://www.justanswer.com/chevy/49d0i-chevrolet-silverado-lt-2010-silverado-ext-cab-lt-need.html Additional triggering option Trigger / activate in reverse (pertinent to cameras or back-up alarms) Some of the original pictures may no longer be viewable. Picture of MBEC with Connector 20791502 inserted into X14 from eBay link above Note 1: Pin 5 has been removed in this image, meaning it is providing 15 amp service Note 2: while not addressed in OP, Pin 7 appears to be used instead of Pin 8 (Pin 7 is described as a fused 10 amp Run/Crank Feed per GM Upfitters: https://www.gmupfitter.com/wp-content/uploads/2021/05/2009_LD_ElectricalPickupsChassisCabs_100813.pdf) And finally, my follow-up questions for anyone: Female GT 280 terminals Delphi Part number 15304711 are listed as being 18-20 gauge, but currently appear to be available in 20-22, 16-18, and 12-14 from multiple sources. I assume the critical element is the size of the wires from the relay pigtail and the size of the terminal for GT 280 terminals will be consistent; does that sound correct? Just to keep it together, if not using the GM connector and don't want to get the GT 280 terminals, (properly insulated) 1/8" female spade terminals will fit according to TahoeYukonForm.com member Gooffeyguy Pin 7 questions: Can Pin 7 be used directly and independently as accessory power without a relay (assuming limiting it to 1-2 devices not to exceed 10 amps)? Can Pin 7 be used as the trigger to only activate the power when running? Can both Pin 2 and Pin 5 be used concurrently (but separately) to power separate circuits (one not to exceed 15 amps and the other independently not to exceed 30 amps)? This becomes valuable with the next question Where are the 10 amp, 15 amp and 30 amp fuses for Pins 7, 2 & 8 in the MBEC X14 connection? The fuses I see in the picture of the MBEC (above) are 25 amp and I assume they came that way (see diagram below - all 4 clearly 25 amp) but Pins 2 & 8 are supposed to be already fused circuits. I have no evidence but the names and corresponding amperage and I don't know what SEO is, so any confirmation of the following information is appreciated. The following numbers are for 2009 Gas Engines [with diesel numbers in parentheses at the end]: I believe the 15 amp Pin 2 fuse is #52 (SEO B1) in the Underhood Fuse Block [#49] I believe the 30 amp Pin 8 fuse is #37 (SEO B2) in the Underhood Fuse Block [#34] I believe the 10 amp Pin 7 fuse is #54 (SEO/ALC) in the Underhood Fuse Block [#51] GMUpfitters identifies these fuses differently than I would expect: SEO B2 [Fuse30A]: Emergency Vehicle Roof Lamp Relay (5Y0) SEO B1 [Fuse15A]: Auxiliary Body Control Module (XBCM) (EXP), Security Indicator Lamp, Vehicle Inclination Sensor, Vehicle Shock Sensor SEO/ALC [Fuse10A]: Not Used Does anyone see any problems using single unit / combination unit relay / fuse blocks? Painless Performance Products (all are 4-pin relays instead of 5-pin): CirKit Boss Auxiliary Fuse Block/3 Circuits (3 Ignition 12V) P/N 70113 https://www.painlessperformance.com/wc/70113 single 40 amp relay with 3 relay-controlled circuits CirKit Boss Auxiliary Fuse Block/7 Circuits (7 Ignition 12V) P/N 70117 https://www.painlessperformance.com/wc/70117 two 40 amp relays, 7 relay-controlled circuits one relay controls 3 in the same housing and the other controls the 4 in the other Appears to trigger both relays from a single input (see manual for 70217 and better image in 70218 linked below): https://www.painlessperformance.com/Manuals/70217.pdf Thus my question above if both Pin 2 & Pin 5 could be used concurrently CirKit Boss Heavy Duty Auxiliary Fuse Block/7 Circuits (7 Ignition 12V) P/N 70118 https://www.painlessperformance.com/wc/70118 two 70 amp relays, 7 relay-controlled circuits Appears to trigger both relays from a single Manual: https://www.painlessperformance.com/Manuals/70118.pdf Larger gauge wiring all around with two 70 Amp SPST relays and total amperage of 140 amps This would require power from the UBEC (Underhood Bussed Electrical Connector) Post 2 or connection to the auxiliary battery if supplying more than the MBEC has capacity for, but triggered by a single source which could be from the MBEC Both 70113 & 70117 available in "Weatherproof version" (meaning they add a rubber cover) as 70213 & 70217. Universal 20A Motorcycle Automotive Fuse Block Fuse and Relay Box Kit with 4 Circuits Low: https://www.amazon.com/dp/B0BM9WFJKL/ This not likely to be my preference but is an option I apologize for the length of this post, but I wanted to try to get all of the questions raised over the last 6 pages in one place. Special thanks to the following members for the additional information they provided in their posts: Diesail (OP) xPosTech Cujo8 Bill in Niantic ZDale59 Oldergeek And also Chevy Mechanic: Goodwrench9124 from www.justanswer.com Edit 7/25/23 ... posted by mistake too early