User Login    
 + Register
  • Main navigation


Lost Password?

Register now!
Fast Search
Slow Search
Google Ad

[Datsun 1200 encyclopedia]

Ignition Switch

From Datsun 1200 Club

Datsun 1200 encyclopedia | Recent changes | Edit this page | Page history | Switch to MediaWiki mode

Printable version | Disclaimers | Privacy policy
Category: Body Electrical System

The Datsun 1200 ignition switch is also known as an "Ignition Starter Switch". For STD models, it is integrated into the Key lock switch. For Super DX and higher grades, it bolts to the back of the key cylinder.

Also see: Keys



How To Use: see Instruments and Controls#Ignition Switch


3-position Export switch vs OPTION 5-position switch:

5-position switch vs 4-position switch:
Note addition of ACC position.

Portugal market:

Interruptor de ignićāo [Ignition switch]
Desligado [OFF]
Ligado    [ON]
Arranque  [START]

Standard Type

STD and some DX models use a non-locking steering column. The ignition switch is mounted via bracket on the dash.


The key lock cylinder and ignition switch are integrated in one unit.
18267.jpg 24036.jpg
Early units had a 3-connector ignition switch. Later units had four connectors.

STD 1200s and DX built for Japan market have a dash-mounted switch (instead of steering column-mounted). The keylock & ignition switch are integrated with only three or four spade terminals on the switch.

25563.jpg 25564.jpg 25565.jpg 25566.jpg

4-terminal keyed 25150-G1001
th_S52-4_ignition-1.jpg th_S52-4_ignition-2.jpg th_25150-G1001-1.jpg th_25150-G1001-2.jpg th_25150-G1001-3.jpg

B210 Van NILES



Part Numbers

25150-H2500 SWITCH COMP.-ignition PB110 DX
25150-H1000 SWITCH COMP.-ignition & starter (up to '71-3)
25150-H1010 SWITCH COMP.-ignition & starter (from '73-8)
25150-G1001 SWITCH COMP.-ignition & starter (up to '78-3)


4-terminal type
BR COIL (for start position)
W  POWER (12V in from Fusible Link)
3-terminal type

4-terminal Wiring

Steering Lock Type

A locking steering column was a Datsun 1200 OPTION for early STD and DX models. It was standard equipment for USA 1200s, JDM GL and GX, and newer JDM 1200 pickups

See main article: Steering Lock


The actual electrical Ignition Switch for this type is removable, and bolts to the back of the key cylinder. In other words, the Ignition Switch is not strictly part of the Lock Cylinder, but connects to it. A rectangular wire connector from the dash harness attaches to the ignition switch.
20003.jpg th_48750-E7705-1.jpg or th_48750-H1900.jpg
Fitment of ignition switch into ASSY-LOCK STEERING

Late (large) vs 1970/1971 (small)
17016_51163ded95bf9.jpgPost 429867 17016_51163dfd7ba15.jpgPost 429867

17016_51163e24b8bb3.pngPost 429867

Switch Part Numbers

48750-H1900 for STEERING LOCK -7803
48750-E7705 ASSY-SWITCH IGNITION (5 POINT) 0471- USA 0 48750-H1900
48750-E4700 for STEERING LOCK 7804- 
* Small type, same as 1980-1982 USA 720

1972-1973 USA
* ACDelco E1406 $38 O'Reillys
* Beck/Arnley 2011174 Rockauto $24



Later 1200 switches interchange with Datsun B310 and several other Datsun models, but not B210.

Ignition Switch Comparison
4973.jpgAlbum 4973
* B110 Small size ~28mm diameter
* B110 Large size ~34mm diameter

TIP: On the back of the switch, each contact is marked ('S', 'IG', etc. molded into the plastic). Double-check before replacing to ensure they are the same.

The larger-diameter switch has two mounting lugs and is used with Keylocks that have an ACC position. 1972 and 1973 1200s use this, all the way up to 1982 B310.
20004.jpgAlbum 20004 20002.jpgAlbum 20002

The small-diameter switch has one bolting lug. And has only four spade terminals without ACC position. It was used on Japan 1200s (USA only for 1971).

Beck/Arnley 2011174 Fits:
Subaru (USA models listed)
* 1982-1987 Brat 
* 1986-1987 GL 
* 1980-1984 DL 
* 1980 GLF 
* 1980 GL 
* 1980-1987 Standard 
* 1968-1973 510
* 1970-1978 240Z, 260Z, 280Z
* 1979-1983 280ZX
* 1972-1973 1200 (B110)
* 1979-1982 210 (B310)
* 1978-1981 510 (A10)
* 1977-1981 810 (Bluebird)
* 1982-1983 Maxima (910 Bluebird)
* 1979-1982 310 (N10)
* 1977-1983 200SX (S10)
ACDelco E1406 ignition switch also fits:
* Same as Beck/Arnley 2011174 except B110, except Subaru
* 1979 Datsun 620
* 1980-1982 Datsun 720


B210 ignition switch does not interchange with B110 per the parts catalogs.

Top: early B110. Bottom: B210
It looks like it would plug into the Small B110 harness, but is wired differently. Beware!

  • AIRTEX 1S6174
  • ACDelco E1478A Rockauto
    • Datsun
      • 1974-1978 B210
      • 1973-1976 610
      • 1975-1977 710
      • 1976-1978 F10
    • Subaru
      • 1985-1989 DL, GL
      • 1985-1987 GL-10
      • 1987 Standard


* Standard Motor Products 1200 US-168L

1200 US-168L
21996.jpgAlbum 21996


The 1971 switch has four spade terminals. The 1972 and newer adds the "Accessory" position and so has five spade terminals.
5022.jpgAlbum 5022
NOTE: The two wires at the front of the Lock Cylinder are for the Key Warning Buzzer system.

ACC Position
ACC on the Ignition Switch feeds only the Radio and the Rear Defroster.

22163.jpgAlbum 22163
Since 1971 didn't get ACC position, 1971 radios connect to Fuse Box 'L' wire (meaning radio can be operated with key OFF)

Switch internal connections
PositionInternal Connection
Off/Garageno connections
Lockno connections, column locked
AccessoryBattery to ACC
RunBattery to ACC + IG
StartBattery to IG + Resistor + Start*
*Starting with 1974 automatic models and all newer, ACC is also hot while in the Start position.

Wiring Table
Switch Wire ColorConnection
WB (Battery)
BWIG (ignition/Run)
BW (LW for B210)ACC (Accessory, not present on 1971 switch)
BY (YB for B210)S (starter)
BRR (resistor)


Ignition Switch Wiring

Where do the wires go on a stock B110?
TerminalConnects to ...
IG (ignition/run)
  • To Ballast Resistor (non-coil side)
  • To IG circuit of fuse box
S (starter)
  • To Solenoid on the starter. On automatic 1200s*, this goes through the Inhibitor Switch
B (battery/hot)
  • From fusible link connected to Battery
R (resistor)
  • To Ballast resistor (coil side)
ACC (accessory)
  • To Radio (through inline fuse)
  • To heated rear window glass (through inline fuse)
*Automatics became available in 1973 in North America.

Common Problems

Start Problems

Ever had the "sometime it doesn't operate the Starter until I turn the key back and forth a few times" problem?

This occurs because the relatively high current loads of the starter solenoid tend to burn the ignition switch Start contacts after some years. This only gets worse. You might think you could prevent this problem by using a relay. The S wire could go to to a relay, and the relay could go from the Main Fuse to the starter. The problem is if the relay sticks, you won't be able to turn it off with the key. To prevent this, you could use two relays, with the main power fed through a relay connected to the IG terminal of the switch. Then if the starter relay sticks, you could turn key to ACC or OFF to stop it.

It is easiest just to replace the switch.

Another common issue is when the key is turned to the 'start' position, and it does not spring back to the 'on' position when the key is released. The switch needs to be replaced in this situation also.

Starts but does not Run

"It will crank and catch fire when key turned to Start, but dies as soon as I release the key to the ON position"

The coil is getting Start current, but not Run current. Causes may include:

  • Ballast Resistor is burned open. It is only use to Run, but not to Start
  • Wiring is loose or bad on ballast resistor
  • Ignition Switch is bad. START position works, but ON does not



You can test the ignition switch with an ohmmter, which is the most direct way. A test light will work too but needs a voltage feed.

  1. Pull the wiring connector off the back of the ignition switch
  2. Unscrew the ignition switch from bracket (early/STD 1200s) or rear of the key lock cylinder (Steering Lock 1200s)
  3. Check ohms between S and B terminals. Should be infinite ohms (no reading)

Turn switch with screwdriver to Start and hold it there. Ohms between S and B should be 0 ohms. If it does not test out correctly, get another ignition switch.


イグニション キー

Retrieved from ""

This page has been accessed 88,836 times. This page was last modified 08:50, 23 February 2022. Content is available under Datsun 1200 Club.