On Daikin air conditioners, L5 is an inverter overcurrent code and E9 is an electronic expansion valve code. Daikin's "Simple Self-Diagnosis by Malfunction Code" list (SM-TS3) defines L5 as "Inverter instantaneous overcurrent (DC output)", with three supposed causes: a defective compressor coil (such as wiring disconnection or insulation failure), compressor startup failure (mechanical lock) and a defective inverter PCB. It defines E9 as "Malfunction of electronic expansion valve coil", with the causes disconnected EEV connectors, a defective EEV coil and a defective outdoor unit control PCB. Both are outdoor unit codes. On RZR-TA and RZQ-TA SkyAir outdoor units, Daikin service manual SiUS281811EA sets L5 at an inverter output current above 59.1 A "even instantaneously" and gives 35-55 Ω between pins 1-4 and pin 6 of the outdoor EEV coil connector.
What does Daikin list for L5 and E9?
| Code | Daikin's meaning | Supposed causes in SM-TS3 |
|---|---|---|
| L5 | "Inverter instantaneous overcurrent (DC output)" | "Defective compressor coil (such as wiring disconnection or insulation failure)"; "Compressor startup failure (mechanical lock)"; "Defective inverter PCB" |
| E9 | "Malfunction of electronic expansion valve coil" | "Disconnection of connectors from electronic expansion valves"; "Defective electronic expansion valve coil"; "Defective outdoor unit control PCB" |
How does the RZR-TA and RZQ-TA manual test for L5?
SiUS281811EA covers RZR18-48TAVJU (cooling only) and RZQ18-48TAVJU (heat pump) outdoor units and their TAVJUA versions. Section 4.41 (p. 269), "Inverter Compressor Instantaneous Overcurrent":
- Detection: "Error is detected from current flowing in the power transistor."
- Decision: "An excessive current flows in the power transistor." The inverter code list (CHECK 9, p. 299) puts it at "Inverter output current exceeds 59.1 A even instantaneously", with the major causes "Liquid sealing", "Defective compressor" and "Defective inverter PCB".
- Supposed causes: "Defective compressor coil (disconnected, defective insulation)"; "Defective compressor startup (mechanical lock)"; "Defective PCB".
The L5 flowchart, in order:
- If the compressor insulation resistance "is 100 kΩ or below", replace the inverter compressor.
- If the compressor coils are disconnected, replace the inverter compressor.
- Run CHECK 4 on the power transistor. If it is not normal, "Replace the outdoor main PCB (A1P)."
- Restart. If the failure does not recur, continue operation ("Momentary power failure is possible."). If it recurs, replace the outdoor main PCB.
- Restart again. If the failure still recurs, "Replace the compressor."
What are the power transistor check values (CHECK 4)?
Section 5.4 (p. 295): power off, remove all wiring from the PCB carrying the power transistors, and measure "10 minutes later after power OFF". An analog meter is recommended; a digital meter with diode check is usable. For some points the manual adds: "Due to condenser charge and so on, resistance measurement may require some time."
| Points (+ / −) | Analog meter, ×1 kΩ range | Digital meter, diode check |
|---|---|---|
| P2 / U, P2 / V, P2 / W | 2 ~ 15 kΩ | 1.2 V and over |
| U / P2, V / P2, W / P2 | 15 kΩ and above (including ∞) | 0.3 ~ 0.7 V |
| N3 / U, N3 / V, N3 / W | 15 kΩ and above (including ∞) | 0.3 ~ 0.7 V |
| U / N3, V / N3, W / N3 | 2 ~ 15 kΩ | 1.2 V and over |
How does the RZR-TA and RZQ-TA manual test for E9?
Section 4.33 (p. 261), "Electronic Expansion Valve Coil Abnormality":
- Detection: "Check continuity of electronic expansion valve coil."
- Decision: "No current is detected in the common (COM [+]) when power supply is ON."
- Supposed causes: "Defective electronic expansion valve coil"; "Defective outdoor main PCB"; "Disconnection of connectors for electronic expansion valve".
The flowchart: cycle power; if the unit returns to normal, it was an "External factor other than error (for example, noise etc.)". Otherwise confirm the EEV connector on the outdoor main PCB (A1P), then check coil resistance (CHECK 18, pp. 309-310). A bad reading means "Replace the electronic expansion valve coil"; a normal one means "Replace the outdoor main PCB (A1P)."
| Outdoor models | Connector (coil) | Pin colors as printed | Measure | Judgment |
|---|---|---|---|---|
| RZR18/24TAVJU, RZQ18/24TAVJU | X21A (Y1E) | 1 White, 2 Yellow, 3 Orange, 4 Blue, 5 none, 6 Red | 1-6, 2-6, 3-6, 4-6 | 35-55 Ω |
| RZR30/36/42/48TAVJU, RZQ30/36/42/48TAVJU | X21A (Y1E), X22A (Y3E) | 1 Orange, 2 Red, 3 Yellow, 4 Black, 5 none, 6 COM[+] Gray | 1-6, 2-6, 3-6, 4-6 | 35-55 Ω |
The outdoor PCB display table (p. 212) splits E9 into "Main" and "Subcooling" detail items. Indoor EEV coils on this system report a different code: A9, "Electronic expansion valve coil abnormality, Dust clogging" (section 4.16, p. 234), with its own indoor coil values in CHECK 18.
Is L5 a stop valve problem?
Not according to SM-TS3: its L5 row does not list a closed stop valve. Closed shutoff valves appear in the check-operation table of Daikin's SkyAir Inverter M Series manual (SiUS25-501, Part 6, section 1.1.3), which covers E3, E4, F3, F6, U3, U4, UA, UF and UH; L5 and E9 are not in it. See our Daikin E3 and E4 article for that table. On RZR-TA and RZQ-TA units, the L5 section does not list the stop valve either, but the E5 section does.
How is L5 different from E5?
In our reading, the two are easy to mix up because both involve the inverter compressor. SM-TS3 lists E5 as "Inverter compressor motor or overheat" with the causes "Inverter compressor lock", "High differential pressure", "Defective inverter PCB", "UVW connection error" and "Defective connector contact". L5 is the instantaneous overcurrent code, and its causes are narrower. A "UVW connection error" appears under E5 but not under L5.
On RZR-TA and RZQ-TA units, E5 is "Inverter Compressor Motor Lock" (section 4.31, pp. 257-258), output "when the inverter compressor motor does not start up even in forced startup mode." Its causes are "Inverter compressor lock", "High differential pressure (0.5 MPa (72.5 psi) and above)", "Incorrect UVW wiring", "Defective PCB" and "Stop valve is not opened". Its flowchart checks the stop valve, compressor cable and U, V, W wiring first, then the same 100 kΩ insulation test, a broken phase, pressure equalization and CHECK 4.
Do these codes read the same on every Daikin model?
The letters match, but the manuals name them differently:
| Code | SM-TS3 (general list) | SkyAir Inverter M Series, SiUS25-501 (contents) | Wall-mounted H-Series, SiUS04-924 (section 4.1) | RZR-TA / RZQ-TA, SiUS281811EA (section 4.1, p. 209) |
|---|---|---|---|---|
| L5 | Inverter instantaneous overcurrent (DC output) | "Inverter Compressor Abnormal" (p. 128) | "Output overcurrent detection" (p. 100) | "Inverter compressor instantaneous overcurrent" (p. 269) |
| E5 | Inverter compressor motor or overheat | "Compressor Motor Lock" (p. 113) | "OL activation (compressor overload)" (p. 82) | "Inverter compressor motor lock" (p. 257) |
| E9 | Malfunction of electronic expansion valve coil | "Malfunction of Moving Part of Electronic Expansion Valve" (p. 116) | No E9 row in its section 4.1 code list | "Electronic expansion valve coil abnormality" (p. 261) |
So the test procedure for your code lives in the service manual for your exact model.
What to check before replacing parts
Daikin's cause lists point to three places for L5 (compressor winding or wiring, the mechanical state of the compressor, the inverter board) and three for E9 (the EEV connector, the coil, the outdoor control board). Our practical advice, not Daikin's wording: start with the cheap items, the compressor lead connections and the EEV connector, then use the winding, power transistor or coil check in your model's service manual to separate the compressor or coil from the board. Do not replace an inverter board and a compressor together without that check; once the insulation and coil checks pass, the RZR-TA and RZQ-TA L5 flowchart replaces the main PCB first and the compressor only if L5 recurs after that.
Parts involved
| Component | Role in this issue | Where to find it |
|---|---|---|
| Inverter boards | A listed cause of L5 ("Defective inverter PCB") and of E5. On RZR-TA and RZQ-TA units the power transistors are checked on the outdoor main PCB (A1P). Listed by part number; match yours by the board on the unit. |
2198390 — Inverter Assembly/control Board 129040J — Inverter PCB Assembly 2007595 — Inverter Assembly |
| Compressors | Compressor coil failure and mechanical lock are listed causes of L5. Compressors are listed by part number; titles do not give the unit model. |
1703496 — Swing Compressor 4005672 — Swing Compressor 150638J — Scroll Compressor 4005908 — Scroll Compressor 2181981 — 208-230v 3 Ph R410a Scroll Compressor |
| EEV coils | The EEV coil is a listed cause of E9. The first title names one outdoor model; the others are listed by part number. |
2313966 — Expansion Valve Coil For RXYMQ36PVJU 2254074 — Coil/elec Exp Valve 2254067 — Coil/elec Exp Valve 2433473 — Coil/el. Expansion Valve 6022924 — Coil For Exv |
| EEV body | Listed by title as an expansion valve and an expansion valve assembly. The titles do not say which models, or whether the valve is sold apart from its coil, so match by part number. |
142054J — Electronic Expansion Valve 6025156 — Expansion Valve Assembly |
| Outdoor control PCB | A listed cause of E9. Match by part number; the title does not say outdoor or indoor. |
6025170 — Printed Circuit Assy (Main) 2371986 — Main Pcb Board |
Scope: This article covers L5, E5 and E9 as listed in Daikin's SM-TS3 "Simple Self-Diagnosis by Malfunction Code" document, whose heading names RA, SkyAir, VRV, PA and Heat Reclaim Ventilator. The table's product columns could not be matched to individual codes in the text we read, so not every code applies to every product. SiUS25-501 and SiUS04-924 are cited only for the entries shown. The detection conditions, flowcharts, 59.1 A threshold, power transistor values and coil resistances come from SiUS281811EA and apply only to RZR18-48TAVJU(A) and RZQ18-48TAVJU(A) SkyAir outdoor units. The parts above are examples listed by live product title, not a fit confirmation.
Before you order
Confirm your unit's exact outdoor model number, the code shown and the part number on the existing board, compressor or coil before ordering. For part-number naming across Daikin Applied, McQuay and Daikin-McQuay listings, see Daikin Applied, McQuay, and Daikin-McQuay Part Numbers: Same Board, Three Names. To browse the ductless and VRV parts we list, see Daikin Parts for VRV Units. Related reading: see our Daikin E3 and E4 article and our Daikin U4 article. To confirm fit, contact us at help@totalhvacparts.com or 302-219-4994 with the model numbers and the error code.
Frequently Asked Questions
What does Daikin error code L5 mean?
L5 is "Inverter instantaneous overcurrent (DC output)" on the outdoor unit. Daikin's SM-TS3 list gives a defective compressor coil (such as wiring disconnection or insulation failure), compressor startup failure (mechanical lock) and a defective inverter PCB as causes.
What does Daikin error code E9 mean, and what should the coil read?
E9 is "Malfunction of electronic expansion valve coil". SM-TS3 lists disconnected connectors from the electronic expansion valves, a defective EEV coil and a defective outdoor unit control PCB as causes. For RZR-TA and RZQ-TA outdoor units, SiUS281811EA gives 35-55 Ω between each of pins 1 to 4 and pin 6 of the coil connector (X21A, and X22A on the 30 to 48 sizes).
Is Daikin L5 caused by a closed stop valve?
SM-TS3 does not list a closed stop valve for L5. Its causes are the compressor coil, a mechanical lock of the compressor and the inverter PCB.
What is the difference between Daikin E5 and L5?
E5 is "Inverter compressor motor or overheat" and includes compressor lock, high differential pressure and a UVW connection error among its causes. L5 is "Inverter instantaneous overcurrent (DC output)" with a narrower list.
Sources
- Daikin Global, Simple Self-Diagnosis by Malfunction Code, SM-TS3 (pages 1-6, list of error codes) (L5, E5 and E9 meanings and supposed causes)
- Daikin Split System Air Conditioners, SkyAir Inverter R-410A Heat Pump 60Hz M Series service manual, SiUS25-501 (Part 6 section 1.1.3, pp. 47-48; Part 7 contents, pp. 113, 116, 128)
- Daikin Inverter Pair, Heat Pump, Wall Mounted Type H-Series service manual, SiUS04-924 (Section 4.1 error codes and description, p. 72)
- Daikin Service Manual, RZR-TA and RZQ-TA Series, SiUS281811EA (error codes p. 209; outdoor PCB display p. 212; A9 p. 234; E5 pp. 257-258; E9 p. 261; L5 p. 269; CHECK 4 p. 295; CHECK 9 p. 299; CHECK 18 pp. 309-310)
- Live product titles for the parts listed above, as shown on each product page
Daikin air conditioning systems involve line voltage, high-voltage DC on inverter boards, pressurized refrigerant and rotating equipment. Service should be performed only by qualified personnel, following the manufacturer's service manual for your model and your facility's lockout/tagout procedures.