Does The Dash Needs Removed From 2002 Gmc Truck To Repair Tow Switch

General Troubleshooting Guide

Equipment

DSD TECH SH-U09C5 USB to TTL UART

On the pictured cable (upside down in this motion picture), you will only utilize White, Gray and Purple leads, tape (or glue) them together with White in the middle, and the other ii on the sides; the other iii are unused. You can either clip the connections of the WGP wires and solder them direct to the lath or solder in leads like the ones pictured and so you can disconnect from the board. Nosotros prefer the connexion method. On the control board, you volition see "R UART T" most the iii console points. RXD GND TXD connects in the opposite society, meaning the RXD on the USB adaptor will connect to T on the board, GND will connect to UART, and TXD volition connect to R. If yours is annihilation similar ours, you will accept to disconnect the colored cable from either the control board or the adaptor BEFORE powering the test demote upwards or information technology will call back you have pressed a key interrupt and prevent the board from loading the test file. Afterward most 5 seconds you can reconnect it. We accept 2 cables that behave this fashion, and ii that do not. Using this with the test bench will allow you lot to get the report on PUTTY similar whatever other COM cable.

Microscope

We have a microscope used to inspect minor resistors and leads; nosotros have an AmScope with a photographic camera, simply y'all tin can find cheaper digital ones that work well enough.

Kester 186 Flux-Pen, CHIPQUIK RMA791 rosin flux container (personal preference)
Lead-Free Solder Paste (8oz container or more, Brand Sure TO KEEP REFRIGERATED and monitor expiration appointment, this stuff will go bad and volition not piece of work)
Yous have a good estrus gun and solder iron, consider J-tip attachments for iron.
Ready of J-tip tweezers; cantankerous locks are nice only not necessary.
Spool of solder wick, a width of at least 2mm, 3mm is expert.
Set of pliers, at least one with needle nose.
Pocket-size battery-operated fans for cooling boards during the soldering process.

Diagnosing Issues

Along with this guide, you should refer to the transmission for S17 diagnostics, other models are slightly unlike, but the theory is the same.

0 ASIC

Unremarkably caused past a bad ASIC or ability failure. Using the RO exam bespeak, check for 1.8V or college starting from the last chip (48) to the kickoff; if yous get a reading of 1.5V or less, in that location is a problem with the ASIC to the LEFT of the point. I.Due east., if the RO betwixt 47 and 46 is reading one.8V, but between 46 and 45 is reading 0.9V, there is a problem with ASIC 46. If you are getting 1.8V across one domain (4 chips vertical) but not on another domain, inspect the 5-pin LDOs on the behind bottom of the board. The lowest i should put out 1.8V or higher (max of 3.3V) on the lesser left pin, and the other should output 0.8V on the same pin. If these are not working check for 3.3V input on the other side of the LDO. If it has iii.3V in only is not outputting correctly, change the LDO. If you cannot get >1.8V anywhere on the board, and your LDOs are not getting 3.3V in, inspect the "Boost Circuit" (refer to the manual) for damaged capacitors and chips, and make sure the entire board is receiving at least 18.0V in. If the Boost Circuit appears fine and there is 18.0V to the board, replace the 24-Pin Film chip designated U3 on the underside of the board well-nigh the power terminals. If you have gotten this far and it still has not worked, I am sorry; y'all have a damaged capacitor on the lath, and it is one of the small ones. You will have to wait for burns, or capacitors that have moved from their locations. If zip appears, you volition have to use a microscope and inspect each capacitor for cracks and fragmentation. These typically occur near the PIC fleck where a lot of power flows, or near your exam points on the chips.

"10" ASIC

These are very straightforward. If the test bench reads out "ONLY Accept 'X' ASIC" more likely than non the bad bit is X+1. For case "Simply Have 31 ASIC" would hateful that ASIC 32 needs to exist replaced.

Temp Sensor Lost / Bad Clock Counter / REG_TYPE (Blueprint NG)

All these conditions relate to a bad pattern. You will have to use the test bench and find out which chip is scoring low and replace information technology. The exception here is the Temp Sensor Lost status, sometimes this can exist stock-still by cleaning off the temp sensor (often replacing it) and the capacitors near information technology. More frequently than not though, an ASIC that is non seated properly will crusade a temp sensor loss because the sensors are fed power FROM the ASIC. Bad Clock Counter you will only encounter in the kernel log, information technology will read something like "BAD CLOCK COUNTER Concatenation 0, ASIC five" this means that ASIC 5 is seated improperly and may be repaired simply by reflowing the solder. REG_TYPE errors are related to a bad pattern, SOMETIMES the test demote will point out what chip caused this trouble, other times the test log will make full up with "REG BUFFER FULL." This indicates that more than than 1 ASIC has a bad blueprint examination and needs to be replaced. SOMETIMES you can replace the EEPROM storage chip (designated U6 on S17) and it will solve this problem.

PIC Lost / Eye Beat out Neglect

These are ALWAYS caused by a Motion-picture show chip failure. If the board is receiving proper 18.0V and it does not work, Replace the 24-pivot PIC scrap U3. If that does not fix information technology, inspect the capacitors nearly the chip.

Replacing ASIC Chips

Bin Numbers

This is the most important factor to consider. The ASIC chips are compatible between the T17, S17, and the plus models (NOT ENTIRELY SURE ABOUT T17E BECAUSE Nosotros DON'T HAVE ANY) then you tin use them from onetime boards within the same 17 family. Nonetheless, labeled on the boards is a sticker that designates BIN number, this can exist Bin1, 2, 3, or 4. You MUST use Bin 2 chips on a Bin 2 board, there is NO compatibility between them. Secondly, but less important, if recycling chips, try to apply boards that pass at a like pattern level; this is designated past the sticker "L1, L2, L3 … L8" When purchasing ASIC chips online, be conscientious and place the BIN number yous are purchasing and marker the pocketbook they come in as before long as you lot get them. There is NO WAY to identify bin number by looking at the chip. (I am sorry about the roll y'all guys have; information technology may exist useless unless you can discover that info.)

Removal

Remove the heatsinks from the summit and bottom of the chip (480 degrees, 50% fan) do not apply pressure level to the heatsinks or you will damage the chip, they should come right off. Apply flux pen to the leads of the ASIC, and some to the bottom (you lot can see air holes underneath) Rut the bit (460 degrees, 25% - 30% fan) direct to a higher place (one-ii inches) until you see the solder menstruation While heating, take J-tip tweezers on the Not-contact edges of the ASIC and option it straight up. Again, not besides much force per unit area, when it is heated enough information technology volition come up right up. Otherwise, yous will damage the flake or PCB. Pick the chip Straight UP every bit best you can, or y'all risk bridging the contacts with solder or knocking a capacitor out of identify. If the chip does not come up off subsequently three minutes of oestrus, it may be fused to the PCB; this happens when a chip gets too hot or receives too much current. Past this bespeak, you may come across the scrap starting to crack or parts of it coming off. Unfortunately, there is no way to save the PCB once this happens, the internal circuitry is damaged. The adept news about this is that near of the other components on the board are reusable then you will have gained a good parts board.

Placing

Start, audit the socket and bit for any solder bridges or areas with low solder. Clear any bridges and utilise the new paste to areas that demand it, heat the new solder until it tins. Check the main pad areas of the socket and flake for high spots and clear them using the solder iron and wick, or the chip volition not sit flat. Use a generous amount of flux to the chip and socket, and double-check your orientation. I like to hold the bit in place with the tweezer first, apply a short burst of estrus until the solder begins to menstruation, I call this tacking. Remove heat and tweezers and the flake should sit where you were belongings it. Apply more flux if needed and apply heat directly above the chip (460 degrees, 25% fan) until the bit sits down, you volition see the solder menstruum onto the contacts effectually the chip. Y'all may take to utilize GENTLE downward force per unit area to the chip to seat information technology properly. If you lot encounter any contacts that look blank, apply a small amount of pressure level to that area during heating. Once placed, allow the board to cool using a bombardment-operated fan or sit it on the tester with the fans on. Check your test points (attached documentation) for their proper readings, if they are good you can run the board on the tester, BUT ONLY ALLOW IT TO DO ASIC COUNT. You can toggle which mode the test runs in the config.ini file on the testing SD card. Alternatively, you can run it until the "nonce" value on the piffling screen changes from 0. (If you have the console cablevision hooked up you tin can encounter where it will read how many ASICs it sees). TURN OFF THE BENCH ONCE It BEGINS THE PATTERN Examination. If you have not reapplied the heatsinks the board WILL overheat and give y'all a bad pattern effect or burnout. If your board is now reading all its ASICs (or a unlike chip is bad at present) y'all tin can reattach the heatsinks to the tiptop and bottom of the chip. Use 480-degree heat, 30% fan above the heatsink and employ NO PRESSURE, the heatsink will seat itself when it is hot enough. Next, run the pattern exam; if everything went well your flake should return a good pattern result. Otherwise, y'all may need to apply more than heat to the chip, reseat information technology, or supercede information technology again. If information technology passes the pattern test with no problems, the board is set up to put into a miner and run.

Skilful Luck!