Dell Latitude 7280 User Manual

Table 11. LED error codes
Blinking Pattern Possible Problem
Amber White
2 1 CPU Failure
2 8 LCD Power Rail Failure
1 1 TPM Detection Failure
2 4 Unrecoverable SPI Failure
4. If there is no failure with the system board, the LCD will cycle through the solid color screens described in the LCD-BIST
section for 30 seconds and then power off.
LCD Power rail test (L-BIST)
L-BIST is an enhancement to the single LED error code diagnostics and is automatically initiated during POST. L-BIST will check
the LCD power rail. If there is no power being supplied to the LCD (i.e., the L-BIST circuit fails), the battery status LED will flash
either an error code [2,8] or an error code [2,7].
NOTE: If L-BIST fails, LCD-BIST cannot function as no power will be supplied to the LCD.
How to invoke L-BIST Test:
1. Press the power button to start the system.
2. If the system does not start up normally, look at the battery status LED:
● If the battery status LED flashes an error code [2,7], the display cable may not be connected properly.
● If the battery status LED flashes an error code [2,8], there is a failure on the LCD power rail of the system board, hence
there is no power supplied to the LCD.
3. For cases, when a [2,7] error code is shown, check to see if the display cable is properly connected.
4. For cases when a [2,8] error code is shown, replace the system board.
LCD Built-in Self Test (BIST)
Dell laptops have a built-in diagnostic tool that helps you determine if the screen abnormality you are experiencing is an inherent
problem with the LCD (screen) of the Dell laptop or with the video card (GPU) and PC settings.
When you notice screen abnormalities like flickering, distortion, clarity issues, fuzzy or blurry image, horizontal or vertical lines,
color fade etc., it is always a good practice to isolate the LCD (screen) by running the Built-In Self Test (BIST).
How to invoke LCD BIST Test
1. Power off the Dell laptop.
2. Disconnect any peripherals that are connected to the laptop. Connect only the AC adapter (charger) to the laptop.
3. Ensure that the LCD (screen) is clean (no dust particles on the surface of the screen).
4. Press and hold D key and Power on the laptop to enter LCD built-in self test (BIST) mode. Continue to hold the D key, until
the system boots up.
5. The screen will display solid colors and change colors on the entire screen to white, black, red, green, and blue twice.
6. Then it will display the colors white, black and red.
7. Carefully inspect the screen for abnormalities (any lines, fuzzy color or distortion on the screen).
8. At the end of the last solid color (red), the system will shut down.
NOTE:
Dell SupportAssist Pre-boot diagnostics upon launch, initiates an LCD BIST first, expecting a user intervention
confirm functionality of the LCD.
72 Troubleshooting

Dell Latitude 7280 Specifications

General

Form factor	Clamshell
Product type	Laptop
Product color	Black
Market positioning	Business
Bus type	OPI
Stepping	H0
Tjunction	100 °C
Processor cache	3 MB
Processor cores	2
Processor model	i5-7200U
System bus rate	4 GT/s
Processor family	Intel® Core™ i5
Processor socket	BGA 1356
Processor threads	4
Processor codename	Kaby Lake
Configurable TDP-up	25 W
Processor frequency	2.5 GHz
Processor cache type	Smart Cache
Configurable TDP-down	7.5 W
Processor lithography	14 nm
Processor manufacturer	Intel
PCI Express slots version	3.0
Processor boost frequency	3.1 GHz
Processor operating modes	64-bit
ECC supported by processor	No
PCI Express configurations	1x2+2x1, 1x4, 2x2, 4x1
Thermal Design Power (TDP)	15 W
Configurable TDP-up frequency	2.7 GHz
Configurable TDP-down frequency	0.8 GHz
Maximum number of PCI Express lanes	12
Memory slots	1x SO-DIMM
Internal memory	8 GB
Memory clock speed	2400 MHz
Memory form factor	SO-DIMM
Internal memory type	DDR4-SDRAM
Maximum internal memory	16 GB
SSD capacity	The Solid State Drive's storage capacity in Gigabytes.
Storage media	SSD
Card reader integrated	Yes
Total storage capacity	256 GB
Compatible memory cards	SD
Number of SSDs installed	1
Intel segment tagging	Home Office, Small Business
Pixel pitch	0.144 x 0.144 mm
Display diagonal	12.5 \
Display brightness	300 cd/m²
Native aspect ratio	16:9
On-board graphics card ID	0x5916
Discrete graphics card model	Not available
On-board graphics card model	Intel® HD Graphics 620
Maximum on-board graphics card memory	32 GB
On-board graphics card OpenGL version	4.4
On-board graphics card base frequency	300 MHz
On-board graphics card DirectX version	12.0
On-board graphics card dynamic frequency (max)	1000 MHz
Audio chip	Realtek ALC3246
Speaker power	2 W
Video capturing speed	30 fps
Front camera resolution	1280 x 720 pixels
WWAN	Installed
Wi-Fi standards	802.11a, Wi-Fi 5 (802.11ac), 802.11b, 802.11g, Wi-Fi 4 (802.11n)
Bluetooth version	4.1
Top Wi-Fi standard	Wi-Fi 5 (802.11ac)
Ethernet LAN data rates	10, 100, 1000 Mbit/s
HDMI version	1.4
Charging port type	DC-in jack
USB 2.0 ports quantity	0
Pointing device	Touchpad
Battery capacity	60 Wh
Battery technology	Lithium
AC adapter power	65 W
AC adapter frequency	50 - 60 Hz
AC adapter input voltage	100 - 240 V
AC adapter output current	3.34 A
AC adapter output voltage	19.5 V
Cable lock slot type	Noble
Password protection type	BIOS, Supervisor, User
Operating altitude	-15.2 - 3048 m
Non-operating altitude	-15.2 - 10668 m
Storage temperature (T-T)	-51 - 71 °C
Operating temperature (T-T)	0 - 60 °C
Storage relative humidity (H-H)	5 - 95 %
Operating relative humidity (H-H)	10 - 90 %
Sustainability certificates	ENERGY STAR
Processor code	SR2ZU
Processor ARK ID	95443
Processor package size	42 x 24 mm
Supported instruction sets	AVX 2.0, SSE4.1, SSE4.2
Intel Identity Protection Technology version	1.00
Intel Stable Image Platform Program (SIPP) version	0.00
Motherboard chipset	Intel SoC

Weight and Dimensions

Depth	207.9 mm
Width	304.8 mm
Height	17.95 mm
Weight	1180 g